Chapter 2 Creating the Summa theologiae
Creating the Summa theologiae
The Life of Thomas Aquinas
We know a fair amount about the life of Thomas, and several good biographies have appeared over the past half century. While we have considerable information about the details of Thomas’s career, given the objective character of his writings, we have almost nothing from him that reveals his inner reflections and feelings. We also need to note that many of the stories about him come from the materials put together for his canonization process, and since hagiography has a different purpose from biography, these need to be used with circumspection. Still, there is much of historical worth in the sources.
Thomas was born in 1225 at the castle of Roccasecca, south of Rome, the son of nobility of the lands of the Emperor Frederick II (1196–1250). His father, Landolph, belonged to the house “de Aquino,” hence his name; his mother, Theodora, was an aristocrat from Naples. Thomas, the last of his father’s numerous progeny from two marriages, was destined for a career in the church. At the tender age of five his family “offered” him to the famed Benedictine monastery of Monte Cassino, where he was brought up as an oblate destined to become a monk and (according to the hagiographers) future abbot of Monte Cassino, given his family’s status in the region. Thomas was thus raised in a monastic environment: the religious life and liturgy formed him in his most impressionable years. Although he preached in his own south Italian dialect, he taught, wrote, and probably often thought in Latin.
Noting his intellectual precocity, when he was about fourteen (ca. 1239) the abbot of Monte Cassino sent Thomas to study at the new university of Naples founded by Frederick II in 1224—the first state university. Here he absorbed the seven liberal arts and began the study of some of Aristotle’s works under the guidance of first-rate scholars, such as Peter of Ireland. The Dominicans were also present at the university and Thomas began to feel a strong attraction to the new order. Sometime around the age of sixteen (ca. 1242) he joined the Dominicans, much to the chagrin of his family. Their opposition led the Dominicans to attempt to spirit him away from Naples to Paris, but he and his companions were overtaken and captured by some of Thomas’s brothers north of Rome. Thomas spent well over a year in a kind of house arrest, resisting his family’s attempts to make him abandon his Dominican garb, and (at least as recounted in the early sources) his chastity, by introducing a comely young woman into his room—whom he drove off with a burning fireplace log. He also profited intellectually from the forced detention, reading the whole of the Bible and beginning to study Peter Lombard’s Books of Sentences.
By 1245 his family relented and Thomas was back on the road to Paris. From 1245 to 1248 the young friar studied in Paris at the Dominican convent of St. Jacques. He probably took courses under the other great intellect of the thirteenth-century Dominicans, the theologian and polymath Albert the Great (ca. 1200–1280). Albert’s capacious mind embraced scientific interests in botany, zoology, and mineralogy, not of concern to Thomas, but he was also a profound philosopher and theologian, important for encouraging the study of Aristotle and of the “Dionysian corpus,” the body of difficult theological works attributed to the “Dionysius of the Areopagus” mentioned in Acts 17:16, but actually composed by a Syrian monk around 500. Thomas accompanied Albert to Cologne in 1248, when the Dominican Order called on Albert to set up a new general house of theological studies (studium generale) for the Dominican convents of Germany. Thomas remained there as Albert’s assistant between 1248 and 1252. Although Thomas does not mention Albert by name in his writings, the fact that he spent seven years with this master had a profound influence on his thought. It is likely that it was in Cologne that Thomas began to act as a “Biblical Bachelor,” teaching introductions to biblical books. His Commentary on Isaiah probably dates to this period and is his earliest theological work.
By 1252 Thomas was in his late twenties and his character and genius were evident. Albert advised the Dominican Master General to send him back to Paris to complete his theological studies. The hagiographical accounts give a consistent picture of the young Italian friar. Physically, Thomas was tall, corpulent, and balding. Personally, he was humble, mild, and gentle. What struck his contemporaries most was his silence and his tendency to what his contemporaries called “abstraction.” Thomas lived in his head, constantly occupied with thinking through theological issues, or “rapt in contemplation,” as the hagiographers understood it. He often seems not to have noticed what was going on around him. An illustrative story of Thomas at this stage is the account of “the dumb ox” (bovus mutus) from his Cologne years. According to this tale, Thomas’s reticence to speak up in the classroom led some of his classmates to refer to him by this title. Albert, however, was impressed by Thomas’s grasp of his lectures on the Dionysian Divine Names and commissioned the young friar to take part in a public disputation. Thomas’s role as Albert’s assistant was to summarize arguments for and against the thesis, but when he offered his own distinction to settle the issue, Albert pressed him vigorously about his solution. Satisfied by his answers, Albert exclaimed, “We call him a dumb ox, but he will still give out such a bellowing in doctrine that it will sound throughout the whole world!”
Another aspect of Thomas’s life noted by the sources, both in his youth and later, was his devotion to prayer. He prayed even more than required by the Dominican daily round of liturgical and personal prayer, and is said to have often had recourse to prayer when confronted by difficult theological problems. The sources are also unanimous that Thomas was characterized from his early years by remarkable powers of memory. He seems to have had what we would call today a photographic memory, that is, he was able to recall word by word almost everything he had ever read. We may take this with a grain of salt, but when one considers the tens of thousands of texts, long and short, cited throughout his works in an age before modern bibliographic or electronic search engines, it is hard to deny that Thomas had phenomenal powers of recall.
The quiet, prayerful, brilliant young friar began to teach at Paris in 1252 as a “Sentence Bachelor” responsible for teaching and writing on the four Books of Sentences. Thomas’s massive Writing on the Books of Sentences (Scriptum super libros sententiarum) was his first major work (it contains almost a million and a half words). Although positions advanced here were later superseded in the Summa theologiae, the testimony of William of Tocco and others on the impact his novel lecturing and writing had in Paris in the early 1250s is telling:
When he was made a bachelor and had begun to pour out in his lectures what he had beforehand chosen to hide in silence, God infused such great knowledge into him … that he was seen to surpass even all the masters [of theology], and, by the clarity of his teaching, to move the students to love of knowledge more than others did. In his teaching he argued new articles; he found a new and clear way of deciding questions; he brought in new proofs in scholastic determinations to the extent that no one who heard him teaching new matters and settling doubtful questions with new proofs doubted that God had enlightened him with a new kind of illumination.
Although there is doubtless a bit of parti pris in one Dominican writing for the canonization of another, it is hard to doubt that Thomas’s Parisian students were “blown away,” as we say, by his brilliance and originality.
Thomas remained teaching in Paris from 1252 to 1259. After several years expounding the Sentences, he was promoted by papal letter to the position of magister in sacra pagina (Master of the Bible) in the spring of 1256 and had to prepare an inaugural lecture and dispute several questions over two days. The lecture, discussing Psalm 103:13 (“Watering the mountains from his places on high, the earth will be filled from the fruit of your works”), gives us a sense of how the young friar understood his vocation. Thomas says that all wisdom comes down from God to water the mountains, that is, the teachers of doctrine. Hence these “mountains,” the masters of sacred scripture, are called to be high in the quality of their lives, enlightened in their lecturing, and well-armed to refute errors. In communicating true teaching to make the earth (i.e., their hearers) fruitful, they do not depend on themselves. “God communicates wisdom by his own power,” says Thomas, “and so he is said to water the mountains by himself; teachers can only communicate wisdom in a ministerial role.” What is worth noting is not only Thomas’s emphasis on the communication of wisdom, but also the humility with which he approached his calling.
Thomas and his contemporary, the Franciscan Bonaventure of Bagnorea (1217–74), who had been promoted in 1253, were not accepted into the lists of the masters until 1257, and then only under papal pressure. The reason was the quarrel that had erupted between the friars and the nonmendicant masters at the university in the 1250s, a controversy that had a considerable impact on Thomas’s thought and career. Religious novelty was often suspect in the Middle Ages, and although the mendicants had won papal support, they had many opponents. The favors the mendicants gained from the popes, both in pastoral care and at the university, provoked a group of secular masters led by William of St. Amour to attack them from 1252 on. The Franciscans and Dominicans were accused of setting dangerous precedents and of being religious hypocrites, even of being the false preachers and forerunners of Antichrist who were predicted to arise at the end of the world (Matt. 24:11–12). The peril was real: the supporters of the secular masters threatened the houses of the friars to the extent that King Louis IX had to call out the royal archers to defend them. On the intellectual side, both orders turned to their rising young stars to answer the charges. In 1256 and 1257 Bonaventure and Thomas wrote defenses of the mendicants, upholding their status as true followers of the “apostolic life” of Jesus and the disciples. While Thomas’s temperament seems to have been basically irenic, his writings against those who attacked the mendicants, as well as later against the radical Aristotelians, show that in polemical situations he could be roused to expressions of anger and exasperation. Nevertheless, Thomas’s mode of engagement was always to encourage discussion, not invective. In a passage from a later work in defense of the mendicant life, the treatise On Perfection written in 1270, he says,
If anyone wants to write against what I have said, it would be most welcome. There is no better way to open up the truth and to refute falsity than to answer opponents, as Solomon says, “Iron sharpens iron, and a person sharpens his friend’s face” (Prov. 27:17). God himself, who is blessed forever, will make the judgment between us and them. Amen.
During the period 1256 to 1259 Thomas taught at Paris as one of the two Regent Masters of the Dominicans, disputing and composing his questions On Truth, perhaps the most significant of his disputations, as well as works like a Commentary on Boethius’s “De Trinitate,” important for its view on the relation of philosophy and theology. We should remember that Thomas, as a member of the Order of Preachers, also preached. Even though he was an academic and not assigned to a parish, he was required to preach Latin sermons to the university community during the year, and, when in southern Italy, he preached to broader audiences in the vernacular. Only about twenty of Thomas’s academic sermons survive, but we have Latin collections of sermons on important religious texts, such as the “Our Father,” the “Hail Mary,” the “Apostles’ Creed,” as well as homilies on the ten commandments (probably originally given in Italian). These sermons show Thomas was a strictly doctrinal preacher, but clear, concrete, and easy to follow. He avoided the lively exemplary stories and rhetorical flourishes found in much medieval preaching.
Sometime in late 1259 or early 1260 Thomas returned to the Roman province of the Dominicans, probably first going to his home convent in Naples. In 1261 he was ordered to the convent at Orvieto north of Rome, which was also the location of the papal court. Thomas was the “Reader of Theology” at this house between September 1261 and September 1265. It was during this time that he brought to conclusion a project he had begun in Paris, what is called in the manuscripts both the Summa against the Pagans (Summa contra Gentiles) and The Truth of the Catholic Faith against the Errors of Unbelievers. In four books (some surviving in his own hand), this work was intended to show that theology could make good use of philosophy in its investigation and defense of revealed truths, both those that have been studied by the philosophers, though often erroneously (books 1–3), and those, like the Trinity and Incarnation, that cannot be attained by reason (book 4). By consensus, this work is Thomas’s other great synthesis, along with the Summa theologiae. In the second chapter of the first book of the work Thomas expresses his intention with a rare personal tone: “Taking up by divine kindness the task of pursuing the office of a wise person with confidence, although it is beyond my powers, my intention is to make known the truth that the Catholic faith professes to the best of my ability by eliminating the errors against it.”
Friar Thomas’s intellectual efforts during these four years extended widely. He completed a long Commentary on Job, one of his most important biblical works, and at the behest of Pope Urban IV wrote a treatise Against the Errors of the Greeks (1263 or 1264), in which he appealed to the Greek Fathers to correct what he considered the errors of contemporary Greeks. It was also at the pope’s request that Thomas began one of his most popular works, The Golden Chain (Catena Aurea), a running commentary on the four Gospels culled from the Greek and Latin Fathers, showing a deep knowledge, unusual for the time, of many Greek writers. Finally, and again at the request of Urban IV, Thomas composed the Mass and Office for Corpus Christi, which was proclaimed as a universal feast on August 11, 1264. Despite some doubts about its authenticity, this collection of readings, prayers, and hymns to the Eucharist (the famous “Pange lingua,” or “Sing My Tongue”) reveals Thomas’s sacramental piety and considerable skill as a poet. On September 8, 1265, the provincial authorities again sent orders to Thomas, commanding him to repair to nearby Rome and the convent at Santa Sabina on the Aventine. It was at Santa Sabina that he began the writing of the Summa theologiae.
During the 1260s Thomas made contact with the new and improved translations of many of Aristotle’s works by a fellow Dominican, William of Moerbeke, who had spent time in Greece and learned the language well. Older claims about Moerbeke’s influence on Thomas are now considered exaggerated, but there is no question that during this decade Thomas deepened his knowledge of Aristotle by beginning to write a series of commentaries on the Greek philosopher. Thomas was to write no fewer than a dozen commentaries on Aristotle in a relatively brief time (ca. 1267–73). In the nineteenth and early twentieth centuries, when Thomas was seen as an “Aristotelian” in outlook, these works were carefully mined to extract an “Aristotelico-Thomistic” philosophy. That view is now disputed, and some have questioned whether we should speak of Thomas as an “Aristotelian” at all (a term he never used). Nevertheless, Thomas knew Aristotle well, cited him extensively throughout his works, and generally followed Aristotle’s philosophical views. But we still can ask why Thomas expended so much energy in writing his commentaries, some quite long, on Aristotle’s writings.
The answer lies in Thomas’s conception of the vocation of the theologian. As he began the writing of the Summa theologiae in 1266, Thomas seems to have become more and more convinced that a careful study of the philosophical resources found in Aristotle could help him deepen his thinking on important theological issues, such as the nature of the soul. He may also have been aware of the growing disputes over the use of Aristotle, the “Aristotelian crisis” that began to disturb the University of Paris in the 1260s. Thomas thought that in the midst of debates over the legitimacy of employing Aristotle in theology, it was necessary to correct misinterpretations and to give students a clear and correct understanding of how the “Philosopher” (as he was named in the medieval schools) could be used in theology, as well as the limits of that use.
In 1268 Thomas was called back to Paris to assume one of the two Dominican chairs of theology. This was an unusual privilege, but the Order seems to have become convinced that Thomas’s presence at Paris was important in the midst of the conflict over the use of Aristotle and the deeper issue of the role of philosophy in theology. Although the teaching of Aristotle’s natural philosophy had been banned at Paris in 1210 and 1215, it proved impossible for both the masters of the arts faculty and the theologians to refrain from employing such a useful intellectual tool, not only in logic, but also more broadly in philosophy. By the 1230s Aristotle was creeping back in, and in the 1240s Albert the Great and others were teaching and commenting on Aristotle and using Aristotelian elements in their theology. Like most medieval textbooks, Aristotle’s writings were used within a “commentarial envelope,” that is, along with the extensive explanations of the Islamic philosopher Ibn Rushd (1126–98), or Averroes. Aristotle’s philosophy, however, especially as filtered through Averroes, conflicted with Christian belief at key points, such as its claim for the eternity of the universe and its denial of personal immortality because of the teaching that there was only one universal Intellect in which all humans participate (monopsychism). Some teachers of Aristotle in the arts faculty, often called “Averroists” (Thomas was the first to use the term) or “radical Aristotelians,” presented Aristotle’s teachings on these controversial points as necessary conclusions of reason, much to the annoyance of conservative theologians who used such claims to attack any use of Aristotle in theology beyond his logic. These theologians, of whom Bonaventure can be considered the founding father, are often called Neo-Augustinians, because they insisted that Augustine’s authority extended equally to both theology and philosophy.
The Dominicans, led by Albert and Thomas, defended a broad use of Aristotle’s philosophy as helpful for constructing a reasonable and coherent account of Christian faith, though, of course, they stood ready to convict Averroes, and even Aristotle, of error when their teachings conflicted with revelation. In this heated atmosphere, with Dominican theology under suspicion by the Neo-Augustinians who stressed the dangers of Aristotle, as well as the presence of Radical Aristotelian philosophers who argued that from the point of view of reason some important Christian doctrines could not be sustained, the Preachers summoned their premier theological mind back to Paris. Another factor in Thomas’s recall was a new flare-up in the attacks on the friars by the secular masters, one that prompted Thomas to write several more defenses of the mendicant life after his return to Paris.
The details of the Aristotelian quarrel cannot delay us here. Suffice it to say that the positions of the Radical Aristotelians, like Siger of Brabant and Boethius of Dacia, were condemned by Stephen Tempier, the Bishop of Paris, in December 1270, while the opposed theological camps of those who were suspicious of Aristotle (mostly Franciscans) and those in favor of using philosophy, including Aristotle despite his problems (mostly Dominicans), were left to fight it out. Many issues were under contention. Two key differences between Thomas and his opponents, such as the Franciscans Bonaventure and John Pecham, involved Aristotle directly or indirectly. The Philosopher had argued for an eternal universe; Christian revelation taught that the universe was created in time (in principio: Gen. 1:1). The Franciscans contended that reason alone could prove Aristotle wrong, while Thomas, against most of his contemporaries, argued that the duration of the universe, that is, whether it was eternal or temporal, could not be demonstrated by reason—creation in time is a truth of revelation. A second major issue concerned the unicity of the substantial form of the human person. Thomas held that the soul was the single substantial form of the body; his opponents believed that a number of different forms or souls (vegetative, sensitive, rational), including a “form of corporeity,” constituted the human person, something like the layers of an onion. Though there had been differing views about this issue, even in the recent past, by Thomas’s time most masters held to a plurality of forms, often citing Augustine (incorrectly) in their favor. The dispute seems arcane to us, but it had implications regarding personal immortality and the status of Christ’s body after death that were important to the scholastics. These quarrels, among others, disturbed Thomas’s second Paris period and continued to dog his reputation after death.
The dozen years 1261–73 in Italy and France saw Thomas at the height of his powers. A number of incidents recounted by the hagiographers provide us with a sense of what he was like. These tales seem to come in part from the witness of Reginald of Piperno, the friar who was assigned to be Thomas’s special companion (socius) from as early as 1259 until his death, functioning as the master’s helper, secretary, confessor, and (in the case of the absent-minded Thomas) what we might call his “minder.” One such story, meant to indicate Thomas’s indifference to worldly matters, rings especially true. It seems one day Thomas and some students walked out to St. Denis in the Paris suburbs to reverence the church’s relics. On their return, as they sat down looking out at Paris, one of the brethren said, “Master, see what a beautiful city Paris is. Wouldn’t you like to be Lord of the city?” “Why,” answered Thomas, “what would I do with it?” The student said that he could sell it to the king to build houses for the friars. “I would rather have the homilies of Chrysostom on Matthew’s Gospel,” responded Thomas. William of Tocco gives some moralizing remarks he ascribes to Thomas about not wanting to be put in a position where his contemplation would be impeded, but the original exchange reveals Thomas’s academic obsessions.
In early 1269 Thomas had less than five years of teaching and writing left. They were to be years of almost incredible productivity, because he was not only continuing work on the massive Summa theologiae, but also teaching, disputing, and writing commentaries on Aristotle and the Bible at an astonishing rate, not to mention various treatises, short and long. Thomas lived in a tearing hurry—he probably thought he never had enough time. Few great thinkers have produced so much material of such quality in so short a time—quite probably to the detriment of his health. Most of the Aristotelian commentaries come from these years. With regard to the Bible, Thomas wrote long commentaries on the Gospels of Matthew and John, the latter possibly his greatest exegetical work. He also composed two important polemic treatises against his opponents. In 1270 his On the Unity of the Intellect Against the Averroists attacked the claim of the radical Aristotelian Siger of Brabant that there is only one Intellect in which all humans participate. In the same year he rebutted John Pecham’s argument that reason alone can prove that the world must have had a beginning in On the Eternity of the World Against the Murmurers. These polemical writings did not preclude Thomas’s obligations of teaching the Bible and conducting public disputations, later put into written form in the Disputed Questions on the Virtues and a number of his Quodlibetal Disputations.
Thomas returned to Italy in the spring of 1272. On June 12 the Roman province assigned him the task of setting up a new studium generale. Thomas chose his home convent for this house of studies. Thus, his life as a Dominican, begun in Naples thirty years before, was to see its last chapter there. In the First Canonization Inquiry of 1319 we are given a picture of Thomas’s daily routine by a layman Nicholas Fricia, who used to hear Mass daily in the Dominican church and attend Thomas’s lectures:
Very early in the morning Thomas would say his Mass in the chapel of St. Nicholas, after which … he heard another Mass, and then, taking off his vestments, at once began his teaching. This done, he would set himself to write or dictate to his secretaries until the time for dinner [midday]. After dinner he went to his cell and attended to spiritual things until siesta, after which he resumed his writing. And so the whole of his life was directed to God. It was the common view … that he had wasted scarcely a moment in his lifetime.
Thomas had little more than a year left in Naples, but it was filled with the same intense activity that marked his second professorship in Paris. He pursued the writing of the Third Part of the Summa, possibly begun in Paris. He continued to lecture on the Bible, to dictate a variety of other works, and, of course, to organize the new house of studies. Along with the ongoing work on the Summa, it seems that most of the commentaries on Paul were either given or revised in Naples, as well as his commentaries on the Psalms. As always, Thomas continued to write treatises, both by request and for his own interests. Among the most important of these was the Compendium of Theology, a doctrinal synthesis organized around the theological virtues of faith, hope, and charity that he wrote for Friar Reginald. He seems to have begun this in his time at Rome, finishing off the chapters on faith. Now he took up the chapters on hope, but death was to preclude completing the work.
Thomas did not get to finish the Summa either. On December 6, 1273, something happened that ended his writing career and seems to have hastened his death three months later. The hagiographical sources provide us with considerable detail about these months, but leave us with many questions. Several sources indicate that when Reginald noted that Friar Thomas was even more abstracted than ever and asked him why he was no longer writing, Thomas replied, “Reginald, I cannot, because all I have written seems like straw to me.” He also expressed the wish that the only thing left for him was death. What is certain is that the immensely productive Thomas never wrote another word and that he seemed even less aware of his surroundings than ever. What had happened?
The medieval lives put the end of Thomas’s writing down to a mystical experience, a foretaste of the vision of God in heaven, the visio beatifica that Thomas had written about so brilliantly. God showed Thomas that however much he strove to penetrate the meaning of the beatific vision, his efforts were nothing more than the merest hint of an explanation (something Thomas himself would not have contested). A mystical experience? Perhaps. Modern investigators, noting the incredible pressures Thomas had been under for the past five years, think that there was also a psychological and/or physical component to the event of December 6, that is, a mental breakdown of some sort, or even a stroke. These medieval and modern explanations are by no means mutually exclusive.
As is customary with medieval hagiography, we are given a detailed picture of Thomas’s last months to demonstrate the sanctity of his death. In January 1274 he received a command from Pope Gregory X to attend the planned council at Lyons, where Thomas’s expertise would have been useful for the attempted reconciliation with the Greek Church. Thomas, Reginald, and their companions began the trip north. During the trip, he struck his head against a fallen tree encumbering the road and was injured (Thomas’s impaired mental state may have had something to do with this). According to one story, Reginald tried to cheer Thomas up by saying that he and his Franciscan contemporary Bonaventure would probably both be made cardinals at the council. Thomas was not amused and told him to be quiet. Providence had other things in store for Thomas. Within a few days, he felt the end was near and asked to be taken to the nearby Cistercian monastery of Fossanova south of Rome in order to be found “in a religious house” when the Lord came for him. Many stories surround his last few days at Fossanova, because the medieval impetus for saint-making was already at work. Two of these stories seem characteristic of the friar: Thomas’s profession of faith in Christ’s presence in the Eucharist, and his express wish to leave his many writings to “the holy Roman Church, to whose judgment I submit all my teaching.” Thomas died on the morning of March 7, 1274.
The fact that Thomas Aquinas was seen by his contemporaries as a saint as much as he was a theologian is evidenced by the fate of his body, the relic of a holy man. The Cistercians of Fossanova were delighted to be in possession of Thomas’s body and to have so many stories about his last days. They soon began to receive pilgrims anxious to pray at the grave of the saint and possibly receive succor and healing. Miracle stories began to spread. Afraid that the Dominicans might steal or commandeer the body with papal approval, they moved it several times and may have cut off the head to keep it should this happen. We know that at one exhumation Thomas’s hand was removed and given to one of the saint’s sisters, though the thumb was later presented to the Dominicans. As ghastly as this all sounds, it fits medieval reverence for the relics of holy men and women. At some time after Thomas’s canonization, the remains were boiled down, and the more transportable bones were eventually given to the Dominicans, who laid them to rest in their church at Toulouse in 1369.
Thomas’s Writings
Thomas Aquinas’s literary output is immense. Granted that his whole life from his mid-twenties was committed to teaching and the composition of works for the training of students and the elucidation of theological issues, it is still impressive to survey the thousands of pages and many millions of words he left to posterity. Although specimens of the friar’s crabbed handwriting (called the littera illegibilis, or unreadable hand) exist, most of his works were dictated to secretaries. (Thomas was said to have been able to dictate different works at the same time, something like a chess master playing several games simultaneously.) We have already mentioned some of Thomas’s writings in the biographical sketch above, but it will be helpful to provide an overview of the more than a hundred works ascribed to him, ranging from short treatises, letters, and sermons, to exhaustive commentaries and immense syntheses.
Something like the devotional triptychs that graced medieval altars, Thomas’s works can be divided into three major sections, or panels. In the center stands the panel of his large syntheses; various commentaries form one outside panel, disputed questions and treatises, short and long, the other. The syntheses include the early Writing on the Books of Sentences of Peter Lombard, the Summa contra Gentiles, and especially the Summa theologiae. Many would also add the unfinished Compendium of Theology here. Medieval theology was always based on lectio, that is, commentary on authoritative texts. Thomas’s earliest synthesis was officially a comment on the Lombard, but, like most scholastics, for him the Books of Sentences had come to serve as a springboard for his own treatment of theological issues. But Thomas was also a powerful commentator in the strict sense. Foremost among these works are his expositions of books of the Old and the New Testaments. Although formerly neglected, they are now considered basic for understanding his theology and have come in for much study in recent decades. His lengthy commentaries on Aristotle are also important, especially for understanding his position in the quarrels over the Philosopher in the thirteenth century.
Correcting the older Neoscholastic emphasis on the purely Aristotelian basis for Thomas’s thought, recent investigators have turned their attention to the Platonic element in his work, for which his commentaries on Platonic (better, Neoplatonic) texts are of importance, especially two works of the late antique Christian Neoplatonist Boethius (On the Trinity, and On the “De hebdomadibus”), as well as on The Divine Names of Pseudo-Dionysius and on The Book of Causes. Although Thomas never wrote any commentaries on Augustine, the African bishop, deeply indebted to Platonism, was his most important theological source, and hence many studies of the Augustinianism of Thomas have recently been produced. The recovery of the Neoplatonic element in Thomas’s thought has been a major achievement of the past generation of Thomist scholarship, but it runs the risk of repeating the mistake of the nineteenth- and early twentieth-century scholars who confidently asserted that Thomas was a “real” Aristotelian. Truth told, Thomas absorbed much from both Aristotle and the Neoplatonists, but he would not have been happy to be termed either an “Aristotelian” or a “Neoplatonist”—nor, of course, a “Thomist.”
The third panel of the triptych consists of Thomas’s investigations into special themes and issues, both individual problems and major themes of theology and philosophy. Thomas’s most penetrating discussions of many issues are often found in his Disputed Questions, especially those he directed to what he felt were the most difficult intellectual problems: What is truth? What is evil? What is the power of God? What is the soul? What are the virtues? These disputed questions can be thought of as the workshops, or laboratories, where Thomas and his students studied the intricacies of speculative questions, weighing the arguments pro and con before establishing the positions he expressed in a briefer form in his syntheses, especially in the Summa theologiae. Where there is overlap between the arguments in the Summa and those detailed in the Questions, the same position is usually adapted, but the Questions give us a fuller sense of why Thomas chose a particular position after considering and rejecting alternative views. One of the delights of studying Thomas is to follow his argumentation from the exhaustive analyses in the Questions to the crisp summaries of the Summa.
The other part of the third panel consists of Thomas’s treatises. Most of these were occasional pieces, responding to issues of the day and often written in response to requests from powerful ecclesiastical or political figures who could not be refused (approximately twenty-six works fit this description). One can imagine that Thomas was not particularly happy with some of these distractions from his more important work, but he did his duty. A few of these treatises have had an impact on various disciplines, such as philosophy, where the early treatise On Being and Essence proved to be very popular (close to two hundred manuscripts). Another popular philosophical work is his response to Siger of Brabant, On the Unity of the Intellect Against the Averroists. In theology his treatise On the Articles of the Faith and the Sacraments of the Church, written in the 1260s, gained a wide audience. In the early fourteenth century Bartholomew of Capua, who had known Thomas at Naples in the 1270s, began to collect stories about him and read his works. Bartholomew compiled a catalogue of the friar’s writings in which he noted, “These writings can be read with ease and profit by everyone, according to his mental capacity. Hence we find even laymen and people of modest intelligence desiring to possess copies of them.” This is strong testimony to Thomas’s impact on a wide readership.
The Plan and Purpose of the Summa theologiae
Imagine a warm autumn afternoon in the year 1266 in Rome on the Aventine hill overlooking the city from the ancient church of Santa Sabina. The church belonged to the Dominican Order, having been granted to Dominic and his followers by Pope Honorius III in 1221. On this afternoon Thomas Aquinas is engaged with his secretaries on a new kind of theological initiative, the book that will be called the Summa theologiae, that is, an ordered synthesis of theology (the title may not be original but appears in most early copies). During his time on the Aventine Thomas and his scribes would complete the Prima Pars of the Summa, consisting of 119 questions and 584 articles dealing with God and creation. In late 1268 Thomas was called back to Paris to serve as Dominican Regent Master for a second time. He would remain there from 1268 until the spring of 1272, teaching and writing at a pace that is still hard to imagine, finishing the largest, or second, part of the Summa. This Secunda Pars was so massive that Thomas split it into two subsections, the Prima Secundae of 114 questions and 619 articles, dealing with the role of human acts in general in attaining beatitude, and the Secunda Secundae of no fewer than 189 questions and 916 articles on human acts in particular in the return process. Considering the Summa alone, Thomas’s productivity during these Paris years is impressive. According to one calculation, he must have written about twelve pages of modern print every day to finish the Secunda Pars. Back in Italy by spring 1272, Thomas worked on the third part of the Summa, managing to finish 90 questions and 549 articles, dealing with Christology and most of the sacraments, before the incident of December 6, 1273, when he stopped writing.
Thomas’s Summa theologiae is one of the great works in the history of Christian thought. In its original form (i.e., minus the Supplementum of 99 questions on the final four sacraments and eschatology compiled by his students from his earlier writings), its three parts consist of no fewer than 2668 articles, or mini-disputations. Each of these mini-disputations follows a standard form: (1) posing the question to be examined (e.g., “Was it fitting for the Word to be incarnated?”), (2) giving a series of arguments against the answer that Thomas intends to support (usually three or four, sometimes more), (3) citing an authoritative text (most often from the Bible) as the proof or principle of the position to be taken (called the sed contra), (4) arguing for his own position in what is called the body of the article (corpus), and finally (5) answering the objections one by one. Sometimes Thomas’s position entails making distinctions concerning the question to be examined, exploring in what sense it can be affirmed and in what sense denied. The fact that whole books have been written about single questions shows that even in its small sections the Summa invites detailed commentary and, quite often, disagreement about Thomas’s meaning. We need to ask why, for whom, and to what purpose Thomas Aquinas undertook this project. Putting the Summa into the historical context of Thomas’s life helps us get a better sense of what he had in mind.
Christian theology, or sacra doctrina as Thomas preferred to call it in the Summa, treats not only eternal truths about God, but also the historical opera reparationis, or works of salvation (Ia, q. 1.7), so it is not illegitimate to ask how Thomas’s own story provides insight into what he sought to do in his great work. Few, if any, Christian theologians made more of the fact that our thinking about God is ineluctably tied to our existence as embodied subjects; human attainment of truth is in and through the body and its senses, though the intellect abstracts the intelligible form from the matter perceived by the senses (Ia, q. 85.1). The tall, corpulent friar sitting in Santa Sabina, later in the Dominican convent in Paris, and finally in Naples, was enmeshed in a rich history that helps us understand what his intentions were in writing the Summa.
Thomas’s growing reputation in the 1260s led to an unprecedented move on the part of his own Roman Province. The Dominican model of educating future preachers, confessors, and teachers was organized according to a carefully orchestrated program of study begun in the individual houses or priories, continued in the provincial houses of study (studia provincialia), and completed for the most gifted students in the studia generalia, the houses of graduate studies, of which Paris was the most important. When the Roman Province summoned Thomas to Santa Sabina in 1265 it seems to have intended him to set up an unprecedented studium personale, a house of study centered on his own teaching, with special privileges granted to students he selected who were guaranteed financial support from the order. He was also allowed to terminate their studies if he judged they were not measuring up.
In his Roman teaching Thomas was required to comment on selected theological texts and to hold disputations at announced times. Ordinarily, he would have lectured on Lombard’s Sentences, and an incomplete fragment of a second commentary on that work gives evidence of this. Thomas, however, soon abandoned this in favor of beginning the Summa theologiae in 1266. Some of the commentaries and disputations he pursued during his years at Santa Sabina seem to have been chosen to help him think through issues he was treating as he progressed in the writing of the Summa. For example, Thomas commented on Dionysius’s Divine Names at Rome in two courses (1265–66 and 1266–67). This theological work, the Magna Carta of apophatic, or negative, theology, profoundly shaped his understanding of divine unknowability found in the early questions of the Prima Pars. Similar correlations between the progress of the Summa and works from Thomas’s later teaching in Paris and Naples are also illuminating.
Did Thomas actually teach the Summa at Rome? Authorities disagree, and the best answer is that we really do not know. We are not even sure if Thomas gave public lectures on the Summa at Paris and Naples; he did, after all, have many other teaching obligations, especially at Paris. Thomas and his select group of students and scribes may have had more than enough to do as they labored away on the new textbook within the context of their own discussions and dictation. On the other hand, Thomas was insistent on the centrality of teaching and the need to create a new model of theological education, so we may wonder why he would not have put this model to the test.
It is clear from the “Prologue” to the Summa that Thomas was quite aware of the break he was making from standard pedagogy and his reasons for doing so. He says,
We have considered that beginners (novitios) in this teaching have been much put off by what has been written by different authors; in part by the proliferation of useless questions, articles, and arguments; in part by the fact that what is necessary for them to know for this science is not set out according to the correct order of learning (secundum ordinem disciplinae), but by what is required for commenting on texts, or for what provides material for disputations; and finally in part because the frequent repetition of these matters causes boredom and confusion in the hearers (Ia, prologus).
The reference to “beginners” has proven puzzling. How could a text so condensed, so brilliant, so deceptively clear be intended for “beginners”? It all depends on what we mean by beginners. It seems most likely that with regard to his immediate audience, the novices Thomas addressed are not to be understood as total beginners in the study of theology, but rather, in accord with the two levels of Aristotelian scientia, they are those who have absorbed the general principles of the understanding of faith through their previous courses on Aristotle, the Bible, and perhaps even Peter Lombard’s Sentences. In other words, these medieval novices are something like modern graduate students in theology. Thomas intends for them to deepen their knowledge and to learn how to introduce other beginners, the faithful, into a better understanding of belief through their preaching and teaching. Thomas may also have had in mind Dominican convent lectors whose task it was to introduce the majority of friars to basic theology.
Given Thomas’s sense of the originality of his project, we can address the meaning of the composition of the Summa by asking what Thomas intended by creating this new model for theological education, and how he conceived of the content and structure of the work. Neither of these questions has a straightforward, or uncontested, answer.
When we ask what Thomas intended, we must remember that he was first and foremost a teacher. The vocation of a Dominican friar was not to sit in the chair of a magister solving questions for the sake of clever answers with an eye to writing texts for the ages, but rather to form students, especially young friars, to become theologians capable of giving good sermons, hearing confessions with accurate theological knowledge, and, if necessary, refuting heretical attacks on Christian faith. A recent line of interpretation of the Summa has argued that the Summa was intended primarily as a new way of presenting moral theology to Dominican students who would soon go forth to preach and hear confessions. In this view, Thomas was reacting to the older Dominican theological formation that concentrated on a moral theology centered on the description of virtues and vices, or on canon law prohibitions of sinful actions. Thomas wished to create a better theological understanding of Christian morality based on the human desire for happiness, as we find it laid out in the Secunda Pars. Thomas realized from the start, however, that it would not be enough just to write another textbook on moral theology, but that sound moral teaching could be successful only if grounded in an integral theology.
This “moral view” of the Summa explains much, but it may be misleading insofar as some might be tempted to think that the Prima Pars is a mere introduction and the Tertia Pars a kind of addendum on Christ and the sacraments. We may well imagine that Thomas came to see the need for a new kind of theological textbook by reflecting on what his Dominican charges needed to become preachers and confessors, without concluding that moral theology was the only or controlling factor in his vision for the work. Rather, as the passage cited above from the prologus suggests, Thomas had come to think that the whole of theological education was out of whack. To see why this was so, we need to look at what Thomas meant by invoking the ordo disciplinae, or pedagogical order, and why he called the subject matter of his work sacra doctrina, not theologia. To that end we need to take a close look at the first question of the Prima Pars, titled “The Nature and Extent of Sacred Teaching,” which introduces the subject matter of the whole.
Sacra doctrina (“sacred instruction”) emphasizes the act of teaching, that is, training minds to master the modes of thinking necessary to command this particular subject matter—what the church believes and teaches. In his earlier (1259) commentary on Boethius’s treatise On the Trinity Thomas had discussed the difference between two kinds of theologia, that of the philosophers, also called scientia divina or metaphysica, and the theologia Christiana based on revelation. By 1266 he had altered his terminology. Although he still occasionally speaks of theologia, his choice of sacra doctrina to describe the content of his new work is significant. Theologia deals with a set of propositions concerning God—scientia as a set of conclusions. Sacra doctrina, however, emphasizes instruction, the generation of scientia (scientia in fieri), that is, how a master trains students to learn a subject according to proper pedagogy, or the ordo disciplinae. As he put it toward the end of the Prima Pars, “A master not only makes his students knowledgeable, but also teachers of others” (q. 103.6). This emphasis on teaching does not mean that content is overlooked, but if we abstract the Summa from the context of instruction and make it a text merely for reading and laying out a set of conclusions about God, we risk perverting Thomas’s purpose, whether he intended the work more as a manual for teachers, or as an actual class text for reading and commentary.
The ten articles that constitute the first question on sacra doctrina reveal the originality and precision of Thomas’s mature thinking on understanding faith. In order to grasp the nature of a discipline one needs to know three things: whether the discipline exists (an sit), the nature of the discipline (quid sit), and finally the method of the discipline (de modo arguendi). Thomas investigates the first issue in article 1. Articles 2 through 7 take up the nature of sacra doctrina, while articles 8 to 10 consider its mode of arguing.
The first article asks, “Whether it is necessary to have another form of teaching besides the philosophical disciplines?” If the many branches of philosophy investigate everything that can be known, culminating in metaphysics (the divine science or theology that investigates God), what need is there for any other kind of knowing or teaching? The key to the answer, as everywhere with Thomas, is teleology—the end or goal determines the means to attain it. For Thomas, the final cause is “the cause of causes,” so if we can demonstrate that something is demanded by the final cause, we have the most strict kind of demonstration (demonstratio propter quid). Thomas does not mount a philosophical argument for God as the final end here, but, in keeping with the nature of the discipline he is investigating, cites scriptural authorities: Isaiah 44:4, proving that God is the final goal that surpasses our understanding, and 2 Timothy 3:16, concerning scripture as divinely revealed for our instruction and salvation. Since God is the goal of humanity as the “good surpassing nature” (bonum supernaturale), and no finite human mind on its own natural powers could ever attain the saving knowledge that leads to the “supernatural” God who is above all that we can know, God reveals this knowledge to humans so that they can be saved.
Sacra doctrina is absolutely necessary for salvation. Its saving content, Thomas contends, must include not one, but two kinds of truths about God—those that surpass reason, such as the Trinity, and also those, like the existence of God, that are open to reason but that are difficult to attain and can be known only imperfectly. Without knowing that God exists, the whole edifice of sacred teaching would collapse, but the same is true for God as Trinity. While Thomas thought that some metaphysicians, even non-Christian ones, had attained knowledge of the existence of God, and while he knew that most humans had some imperfect conception of god or gods, all these convictions, from the crudest to the most profound, had no saving power. This insight displays the grandeur and the misery of metaphysics: it is the highest form of human knowing and natural contemplation, but it is always flawed and without salvific effect.
Thomas uses reason and philosophical modes of arguing throughout the Summa, but it is not a work of philosophy, or even of philosophical theology. The Summa theologiae is fundamentally a work of doctrinal theology, however much it makes use of philosophy and philosophical theology (i.e., metaphysics). Since sacra doctrina is a true science, it needs to make use of both reason and faith, of philosophical and theological argumentation. If philosophy and theology are necessary, however, they are not equally necessary—only revelation and the faith based on it are salvific. Etienne Gilson expressed the nature of this form of theology well when he said, “[I]t is of the essence of the theology called ‘scholastic’ that it appeals freely and widely to philosophical reasoning. Because it draws on faith, it is scholastic theology, but because of its distinctive use of philosophy, it is scholastic theology.”
Thomas could not be clearer about the necessity of sacra doctrina for salvation, but his insistence raises a problem that again emphasizes the centrality of teaching and learning. If sacra doctrina is needed for salvation, does this mean that Thomas and his advanced students alone will be saved? What about the illiterate old lady in the back of Santa Sabina during morning Mass? Will she have to pay tuition and start a theology degree (per impossibile for a woman in the medieval church)? This reductio ad absurdum shows that all believers have to share in the activity of sacra doctrina, that is, in being instructed and learning the truths of faith to the best of their abilities. Since the source of sacra doctrina is God’s infinite self-knowledge, the difference between all our finite receptions of such knowledge, whether those of Thomas and his students or of the old lady in the back of the church, sink into insignificance. For Thomas what they (and we) all need to have in order to be saved is willingness to be instructed.
The stage is now set for Thomas to investigate what kind of discipline sacra doctrina is. Article 2, which asks whether sacra doctrina is a science in the Aristotelian sense, has been the source of much discussion. Many thirteenth-century theologians had investigated whether theology could be considered a science, usually answering that it was so only in an imperfect sense, because of several difficulties in squaring the strict Aristotelian notion of science as found in the Posterior Analytics with the Christian “understanding of faith.” Thomas was one of the few who insisted that sacra doctrina was indeed a real scientia in the Aristotelian sense. We must remember that this is far from the modern sense of empirical and experimental sciences. For Aristotle scientia is “sure knowledge through causes,” best illustrated by rigorously deductive disciplines, such as mathematics or geometry, that is, organized bodies of knowledge in which indisputable principles lead by syllogistic reasoning to necessary conclusions. Thomas argues that sacra doctrina does, indeed, meet the essential requirements of Aristotelian scientia in that it argues from principles revealed by God, shows the causal relationships among revealed doctrines, and demonstrates new conclusions. It is important to note, however, that Thomas does not cite Aristotle as his authority for this, but rather Augustine on “wisdom as the science of human and divine matters” (On the Trinity 14.1.3), already hinting that sacra doctrina is a science because it is wisdom.
Thomas goes beyond Aristotle in how he conceived of scientia as an analogous term, one capable of being understood in a variety of ways. Several shifts in meaning from Aristotle are important to note. For example, Aristotle allowed for “subalternate” sciences where one body of knowledge depends on premises known from another (e.g., for ancient thinkers music depended on mathematics), but sacra doctrina is a science subordinate to a science we cannot know, namely, God’s supreme, nondiscursive self-knowledge. Another difference is that in Aristotle’s view sciences were either speculative (i.e., contemplative) or practical, directive of action; for Thomas, sacra doctrina, although primarily speculative, is both speculative and practical (a. 4), that is, it deals essentially with God and secondarily with human actions.
It is clear that sacra doctrina is an unusual “science,” one that while it may fulfill the basic premises of Aristotle’s view of science as sure knowledge, stretches Aristotle beyond what he would have recognized. The reason for the unique nature of sacred teaching is manifest in article 6, which is the key to the whole first question: “Is Sacred Teaching Wisdom?” In order to understand why sacra doctrina is wisdom we can turn to Thomas’s earlier Summa contra Gentiles, where he offers a reflection on the vocation of the Christian theologian in the first two chapters. Considering the theologian as the student of divine wisdom, Thomas says,
Just as it is proper for the wise person especially to meditate on the truth about the First Principle and then to consider other things, so too he has to attack the falsity contrary to it. This is why it is fitting that the twofold task of the wise person (sapiens) is proclaimed by the mouth of [Divine] Wisdom in the passage cited (Prov. 8:7): to speak the divine truth that has been meditated upon … , and to attack any error against truth. (SCG I.1)
All of Thomas’s writings, but especially the Summa theologiae, were attempts to fulfill his vocation of a teacher of wisdom.
Wisdom is a fundamental theme of biblical teaching enshrined in the Wisdom literature of the Old Testament and especially in Paul in the New Testament, who often contrasts the wisdom of this world with the wisdom of God (Rom. 8:6; 1 Cor. 1:20–21, 2:6). Aristotle had identified wisdom in the philosophical sense as the habit of knowledge that puts things in their proper order (sapientis est ordinare et non ordinari). Augustine also made much of wisdom, especially in books 12 and 14 of On the Trinity, where he treats the superiority of divine wisdom over the science of earthly things. Thomas’s teaching on wisdom is an original synthesis of these sources.
Sacred teaching is wisdom, Thomas says, because “it belongs to the wise person to order and to judge” (art. 6), a constant theme in his teaching. Ordering and judging are rooted in the essential act of wisdom, that upon which all its ordering and judging depend, namely, contemplation: “Wisdom considers [i.e., contemplates] the very object of happiness, the highest intelligible being” (IaIIae, q. 66.5, ad 2). Aristotle analyzed wisdom as the intellectual habit that orders and judges all the disciplines, but Thomas also found this teaching in Paul, who said, “The spiritual person [i.e., the wise person] judges all things” (1 Cor. 2:15). A science does not establish its own principles, but as sapientia sacred teaching not only establishes its principles from revelation, but also explains them insofar as it can, defends them against attack, and judges the first principles and conclusions of the other sciences. As wisdom, it also orders all the principles and conclusions of revealed teaching, connecting the truths to each other and arranging them in the best way to achieve the goal to which they are directed, the pursuit of eternal happiness. Since wisdom puts things in order, and all ordering is effected in relation to an end or goal, the whole teleological structure of the Summa is the expression of Christian sapientia. Such wisdom follows the model of the most perfect form of movement, circular motion, by beginning from principles, arguing to conclusions, and returning to the principles with deeper understanding.
Article 6 says that sacra doctrina makes use of philosophical sapientia, which judges and orders things from the perspective of the highest cause as known from creatures (Rom. 1:19 is cited), but that it depends primarily on the higher wisdom of the Bible “in relation to what is known to God alone about himself and communicated to others through revelation.” Thomas, however, distinguishes this form of revelation-based wisdom that can be cultivated by study (per studium) from the highest wisdom, the gift of the Holy Spirit, by means of which believers come to know divine matters through connaturality (art. 6, ad 3). There are then three kinds of sapientia, with the sapientia that is sacra doctrina occupying a middle position between the acquired natural wisdom of metaphysics and the infused wisdom that comes from the Holy Spirit. The ordo doctrinae and ordo disciplinae set forth in the Summa form two sides of a sapiential ordering based on the revelation found in the Incarnate Word. Sapientia is central to understanding what Thomas intended in writing the Summa.
Having established that sacra doctrina is the highest sapiential science, Thomas turns to how sacred teaching functions in the last three articles in question 1. Science in the Aristotelian sense is “argumentative” (argumentativa), that is, it uses reason to argue from principles to conclusions. Sacra doctrina is also argumentative (art. 8), but once again with a twist. For Aristotle, the supreme human science of metaphysics depends on principles that are inherent in human knowing, such as the principle of contradiction (i.e., that something cannot be both true and false under the same aspect at the same time). Human thinking presupposes but does not prove these essential truths. In the case of sacred teaching, however, the human mind accepts truths on the authority of God revealing, although these truths are by no means self-evident (e.g., that the one God is a Trinity of persons). Having accepted these truths as principles, the sapiential theologian can defend them against attack and deduce further insights for believers. Hence, sacred teaching argues in different ways for different audiences. In the case of those who do not accept revelation, it can only rebut arguments that the articles of faith are totally incoherent or contradictory. With those who accept revelation, but have gotten some of its teaching wrong (“the heretics” for Thomas and his contemporaries), it can argue from the articles held in common to the truth of those under dispute. Finally (and most important), for believers, its arguments make manifest the implications of faith, following the Augustinian program of “faith seeking understanding.”
Thomas sums up his conviction about the importance of reason for sacra doctrina in the famous formula: “Since grace does not take away nature but perfects it, it is necessary that natural reason serve faith, just as the natural movement of the will serves charity” (a. 8, ad 2). A passage in his Commentary on Boethius’s “On the Trinity” puts it this way: “Those who make use of philosophical teaching in sacred teaching by redirecting them to the use of faith do not mix water with wine, but rather change water into wine.” Thus, in its form of arguing sacred teaching uses both principles based on authority, which in the case of a revealed science are the strongest kind, as well as principles from philosophy, though these are external and only probable in matters of faith. Nevertheless, in each mode Thomas makes use of the mind’s inherent dynamism to move from premises to conclusions. What he does not advert to in this discussion, perhaps surprisingly given its importance throughout the Summa, is the distinction between arguments concerning revealed truth that can be considered necessary (ex necessitate) and arguments from fittingness (ex convenientia). For example, it is a revealed premise that Jesus Christ is fully God and fully man. Hence, it follows by logical necessity that Jesus must have both a divine will and a human will. However, there is no necessary proof for the fact of the Incarnation itself. God did not have to become man. Given that the Incarnation is revealed in the Bible, however, sacra doctrina allows the believer to explore fitting reasons for why God chose to take on human nature.
Finally, sacra doctrina is scriptural, that is, it is based on the authority of God found in the Bible (aa. 9–10). Thomas uses sacra doctrina and scriptura interchangeably in question 1. If God’s revelation is the efficient cause of sacred teaching and salvation the final cause, the instrument revelation uses to convey this knowledge is the Bible, the written word of God. Here another problem surfaces. Sciences in the Aristotelian sense make use of textbooks that are rigorously logical (think of Euclid’s Elements), but the Bible is filled with stories and metaphors—scarcely a “scientific” book. But, Thomas responds, it is quite fitting for God to use metaphors and corporeal language in conveying his message, both out of necessity because the Bible is directed to all people (not just philosophers), and because it is useful for drawing people to the knowledge of higher intelligible realities through lower sense images (a. 9). But there is an even deeper reason, as shown by the two citations of Dionysius that appear in article 9. Dionysius was aware not only that metaphorical language was necessary out of condescension to our human way of knowing by concrete realities and images, but also that it was important for indicating God’s transcendence. Employing philosophical terms like being and goodness and the like might tempt the theologian to think that these concepts can give us knowledge of God’s essence. No, says Thomas, this kind of philosophical language “Tells us more about what God is not than what he is; likenesses of the things that are farther away from God give us a truer sense that he is beyond what we say and know of him” (a. 9, ad 3). The true wisdom of the theologian is to know that he or she does not know. Paradoxically, the fact that sacra doctrina is essentially scriptural also shows that it is fundamentally negative.
Sacred teaching mediates the transformation of the pictorial language of the Bible into an intelligible scientific account through biblical interpretation. Thomas briefly discusses this in article 10, where he notes the traditional four ways of reading the biblical text, the literal (i.e., what God intended by these words), and the three spiritual senses built upon the letter (the allegorical concerning Christ and the church, the moral concerning human action, and the anagogical pertaining to heaven). He insists that the key to reading a text is the “intention of the author” (intentio auctoris). But God is a unique author, because God alone can write on two levels. The words he communicates through the human author as instrument have a literal meaning, and, insists Thomas, the “letter” of the text is often a metaphor that needs to be decoded (e.g., when the Bible refers to “God’s arm” it is signifying his power). But the spiritual meanings are also part of God’s intention because only God, who controls history, can bring it about that certain things (events, persons, etc.) described in the Bible have meanings that indicate other realities. Nevertheless, Thomas insists that in the practice of sacra doctrina arguments (in the true, deductively necessary sense) should be drawn only from the literal sense. This should not be treated as a kind of exegetical straightjacket, because it is clear that Thomas maintained that because human meanings cannot exhaust the divine truth, at least some biblical passages could have a number of literal meanings. Furthermore, Thomas’s “literalism” does not preclude all use of spiritual readings in sacra doctrina, and he employs a number of spiritual interpretations throughout the Summa. Strictly speaking, it seems that such citations should be considered arguments from fittingness (ex convenientia), not from necessary deduction.
The modern reader of the Summa will be hard put to think of the book as scriptural, because Thomas’s use of the Bible is far from our own way of interpreting scripture. However, the Dominican cites scripture more than any other source over the course of the Summa, not only in the authorities quoted in the sed contra sections of the articles that are the basis for his arguments, but also in his explanations, arguments, and responses. Thomas did his theology with the Bible at hand (or in his head), and he insisted that the Bible be read ecclesially: “Faith inheres in all the articles of belief because of one mediation, namely because of the First Truth proposed to us in the scriptures understood according to the church’s correct teaching” (IIaIIae, q. 5.3, ad 2). When we turn to his biblical commentaries for further elucidation of his hermeneutical practice, once again we enter a foreign world, because Thomas is little concerned with the narrative or rhetorical structure of the scriptural books the way that modern biblical scholars are. Rather, he seeks to bring out the doctrinal intelligibility of the revealed message (the propositum) by organizing the chapters of the biblical books into comprehensive patterns, especially through what he called “the division of the text,” which teased out (some might say “imposed”) a scientific structure on the biblical narrative. This process of making the stories and metaphors of the Bible scientifically clear, more evident in some commentaries than others, is foreign to modern exegesis, but it reveals three essential principles for understanding Thomas’s view of sacra doctrina. The first is that holy teaching is always fundamentally biblical. The second is that the nature of the Bible as God’s words directed to humanity must be narrative and metaphorical. The third (the one that we do not share today) is that the role of the magister in sacra pagina is to transform biblical narrative and metaphor into a form of articulated scientific discourse to reveal its intelligibility. Thomas’s notion of sacra doctrina is paradoxically always both scientific and scriptural. As he put it in his Quodlibetal Question VII.6.1, “Sacred scripture was divinely handed on for this purpose: so that through it the truth necessary for salvation might be made manifest to us.”
What, then, is the order of the sapiential teaching of sacra doctrina set forth in the Summa theologiae? This is a question that looks easy to answer, given the linear and carefully articulated structure of the work, but it is one that has proven to be a bone of contention. The issue is important, however, because both the order of what is to be taught (ordo doctrinae) and the order of how to teach and learn it (ordo disciplinae) were crucial to Thomas’s decision to write a new theological textbook. The two forms of ordering are in reality two sides of the same coin.
In thinking about the ordering of the Summa, it is helpful to distinguish between what have been called the “micro-structures” and the “macro-structures” of the work. The ordering of the Summa is evident on both levels, that is, on the micro-level in how Aquinas marshals axioms, principles, definitions, distinctions, divisions, reasons, causes, and questions to attain conclusions that are the starting points, or principles, for further explorations. One of the dominant features of the work is the constant internal cross-referencing by which Thomas builds later arguments on earlier conclusions. The relationship of principles to arguments and conclusions, inherent in the logic of the scholastic quaestio, reached a culmination in the Summa. “Each question,” says Bernard Lonergan, “called for a statement of principles of solution and for the application of the principles to each of the authorities invoked. But a series of questions on a single topic, such as De Veritate, De Potentia, De Malo, demanded a coherent set of principles for all solutions on that topic, while a Summa needed a single set relevant to every question that might be raised.” Hence, the inherent ordering of the smallest micro-structures shapes the articles that are grouped into questions, and questions clustered into topics, or what have been called treatises (Thomas did not use this term), such as the “Treatise on Law,” or the “Treatise on Christology.”
This sapiential ordering is also evident on the level of the most general “macro-structure,” that is, the overall plan that Thomas had in mind, especially in dividing the Summa into three parts. In 1939 Marie-Dominique Chenu proposed a solution to how the work is structured that has a good textual foundation in the Summa. At the beginning of question 2, Thomas says that “the principle intention of this sacred teaching” involves not only God as he is in himself, but also as the beginning and end of creatures, especially rational creatures. Therefore, “with a view to laying out this teaching we will first treat of God; second, of the movement of the rational creature to God; third, of Christ, who, as man, is the way for us in journeying to God.” This description of the three parts reflects the model of exitus-reditus, that is, the flowing out of all things from God and their eventual return to him, a model Thomas had already appealed to in his Writing on the Sentences. Actually, by speaking first of “how God is in himself,” and then how God is both the source and the goal of all things, Thomas seems to be implying a threefold, originally Neoplatonic, model that he would have known through the writings of Pseudo-Dionysius, comprising (1) God in God-self; (2) the exitus, or procession of creatures from God; and finally (3) the reditus, or the return of creatures to God. Both God in himself and the procession of creatures from God are found primarily in the Prima Pars, while the return of all things to God is spread over the Secunda Pars and Tertia Pars. This view has won considerable acceptance, although it has had its critics. However, it should not be applied in a rigid fashion. First of all, God’s creative power and his role as the end of all things are found throughout the Summa. Furthermore, the exitus-reditus model does not preclude the presence of other structuring themes at work in the book, such as the various kinds of causality, the role of Divine Goodness, the notion of exemplar and image, and the forms of grace. In sum, we might say that several overlapping structural principles are at work in the Summa, each providing insight into the mind of Thomas.
The organization of the Summa has been criticized, notably by those who question whether the triple paradigm threatens to reduce sacra doctrina to an abstract philosophical account having little contact with the history of salvation revealed in the Bible. Other critiques come from those who note that the Secunda Pars with its great length seems almost to submerge the other parts, as well as from those who have wondered if Thomas’s teaching about Christ, the core of Christian theology, appears to be a kind of afterthought to the basic structure. Nevertheless, understanding the Summa as based on the cycle of emanation and return helps tie much of Thomas’s theological work together, from the Writing on the Sentences to the Summa. In his earliest synthesis Thomas had already referred to the coming forth from and return of all things to God as a key theological principle, but the structure of the Lombard’s work did not allow him to use this great circle (circulatio vel regiratio) as a structuring principle. Thomas also refers to the exitus-reditus model in other works. The Summa contra Gentiles seems to depend on it, though in a less evolved way than the later Summa.
For Thomas this circular motion reveals God’s sapiential ordering on the most universal level. To think of the exitus-reditus model as primarily philosophical and Neoplatonic, as some have argued, is a modern view that Thomas would not have shared. What else does scripture teach but how all things were created by God and are directed back to him as their final goal? What else does Christ mean in the Apocalypse when he says, “I am the Alpha and the Omega, the first and the last, the beginning and the end” (Apoc. 22:13)? Furthermore, the Dionysian Divine Names that Thomas was teaching at the same time he was writing the Prima Pars was the foremost Christian, quasi-apostolic, source for the triple pattern of (1) God in God-self, (2) God as producing all things from his Goodness (exitus), and (3) God as the universal goal of reditus. Thus, the exitus-reditus model had a good scriptural and Dionysian pedigree that would have recommended it to Thomas.
What about the history of salvation and the role of Christ? Once again, we must beware of anachronism or of importing our problems into Thomas’s world. Just because the Dominican chose not to follow the mode of presenting Christian faith according to a narrative historical paradigm, such as that of the “work of creation/work of restoration” (opus creationis/opus recreationis), does not mean that he thought the order of sacra doctrina excluded an integral role for sacred history. Rather, it has been argued that the exitus-reditus schema in its inner structure is by definition open to history, even determinative thereof. For Thomas, there was no conflict between the best mode of teaching (ordo disciplinae) and the ordo rerum, or structure of saving history. Both were expressions of divine sapientia, and both were integral to the fabric of the Summa. Aristotle’s view of scientia excluded temporal events; Thomas’s sacra doctrina necessarily included the events of the course of salvation as recounted in the Old and the New Testaments, though historical events revealed their scientific intelligibility only in the light of revelation. This is why the argument ex convenientia, that is, from fittingness, plays such a large role in the Summa, especially in the treatment of Christ and the sacraments. The free events that constitute the history of salvation do not proceed from necessary causes, but when God brings them about, we can see how fitting they are in the light of sacra doctrina.
This perspective may also help us in responding to two of the other questions addressed to the structure of the Summa noted above: Why is the Secunda Pars so quantitatively dominant? And why is Christology, the teaching about Christ, placed at the end, instead of being foregrounded? We need not agree with Thomas’s decisions here, but we can at least appreciate the reasons he had for making them. The moral interpretation of the Summa answers the first question by noting Thomas’s intent to train preachers and confessors, but this need not exclude a deeper view. For Thomas, the historical situation within which we are called to participate in the sacra doctrina necessary for salvation is the present time in which we must practice virtue and avoid vice as we direct our lives toward the goal of human existence, the beatific vision. Despite its length, its intricacy, and its at times numbing detail about many issues no longer relevant, the Secunda Pars is a treatise on how to live and how to guide others in living. How far we might want to adopt Thomas’s structure for living today, or to replace it with something new, are valid questions, but these do not affect why Thomas put so much effort into the Secunda Pars.
In the case of Christology, Thomas would probably have been surprised at objections to his placing Christ in the Tertia Pars. As he says in the Prologue, “Because our Savior the Lord Jesus Christ, … showed the way of truth to us in his very self through which we might attain the happiness of eternal life by our rising again, it is necessary that as the fulfillment of the whole business of theology (ad consummationem totius theologici negotii), after the consideration of the final end of human life and the virtues and vices, our treatment of the Savior himself and his gifts to the human race should follow.” Thus, Thomas clearly thought that the Tertia Pars was a culmination, not an afterthought. The immense Secunda Pars about attaining the final goal of human living would mean nothing without Christ, who makes it all possible. The last part is the best part, in Thomas’s view.