Augustine in His Own Words
we must dispute the view that maintains that our nature has been weakened and changed through sin. I think, therefore, that before all else we must inquire what sin is. Is it some substance? Or is it a name wholly lacking substance, by which is expressed neither a thing nor an existent nor some kind of body, but the action of doing something evil? I believe it is the latter, and, if it is, how could that which lacks substance have weakened or changed human nature? . . .
(21.23) Those for whom you seek a physician are in good health. And not even the first man was condemned to death for such a reason, for he did not sin afterwards. . . . His descendants also are not only not weaker than he, but have actually fulfilled more commandments, since he neglected to obey even the one. . . . (30.34) How can people be answerable to God for the guilt of a sin which they know is not theirs? For if it is necessary, it is not theirs. Or if it is theirs, it is voluntary; and if it is voluntary, it can be avoided.62
(iii) Salvation Outside Christianity
Pelagius argued for the possibility of salvation beyond the borders (whether temporal or geographical) of Christianity. From Pelagius, On Nature, as quoted in Augustine, On Nature and Grace:
(2.2) Even if, in some nature or in some past time, faith in the blood of Christ was not known to [humanity], God is not unjust and would not deprive the just of their reward for justice if the mystery of Christ's nature as both human and divine, which was manifest in the flesh, had not been proclaimed to them. . . . For there still exist some people in remote places, although it is said that they are few in number, to whom the Gospel has not yet been preached—what should human nature do or what has it done, either before, when it had not yet heard that salvation was to come to pass, or now, if it has not learned that it was accomplished? What should it do except fulfill God's will by believing in the One who made heaven and earth and who created human nature itself (as it is naturally perceived), and by living rightly, even though it has not been tinged with any faith in the Passion and Resurrection of Christ?63
62. Quoted in nat. et. gr. 9.10–30.34 (BA 21:258–306); trans. Mourant and Collinge, FOTC 86:28–47. Note the final syllogism. Caelestius, in a book of syllogisms entitled Definitiones, argued in a similar vein: "We must ask whether a person ought to be without sin. Undoubtedly, one ought to be. If one ought to be, one can be. If one cannot be, then one should not have to be. And if a person ought not to be without sin, then the person, therefore, ought to be with sin; and then sin will no longer be sin. . . . Or if it is absurd to say that, then it is necessary to admit that a person ought to be without sin, and it is obvious that one is not obliged to do more than one's ability" (quoted by Augustine, De perfectione justitiae hominis 3.5, CSEL 42:6; my trans.).
63. Quoted in nat. et. gr. 2.2 (BA 21:246–48); trans. Mourant and Collinge, FOTC 86:23–24.