The One Christ: St. Augustine's Theology of Deification (continued)
The Holy Spirit's Indwelling 143 cause standing in the middle of this illuminating section on how to speak of the Trinity properly is a very succinct and helpful passage relating to how Augustine understands the Holy Spirit. As we just saw, Book 6 opened with the Arian claim that 1 Cor. 1:24 essentially bifurcates the Father and the Son. The Father is powerful or wise, not in himself, but only in the Son, leading to the conclusion that the Father "will be great with the greatness he has begotten, and good with the goodness, eternal with the eternity, omnipotent with the omnipotence which is born from him," and so forth.21 Ultimately this discussion centers on the way to understand unity rightly. This is why Augustine next turns to a discussion of various types of union, citing John 17:22 on the unity between Christ and his followers, and 1 Cor. 3:8 on the equality of the one who waters and the one who plants. He then lists three more types of unity: the hylomorphic unity between body and soul, the nuptial unity between man and woman, and the divine unity between Christians and the Holy Spirit.
Augustine next shows how the Holy Spirit is likewise to be given the same unity and equality of substance [in eadem unitate substantiae et aequalitate] within the divine Trinity as the Father and the Son:
For whether he is the unity of both the others or their holiness or their charity, whether he is their unity because their charity, and their charity because their holiness, it is clear that he is not one of the two, since he is that by which [Father and Son] are joined to the other, by which the begotten is loved by the one who begets him and in turn loves the begetter. Thus They keep unity of the Spirit in the bond of peace (Eph. 4:30), not in virtue of participation but of their own very being, not by gift of some superior but by their own gift. We are bidden to imitate this mutuality by grace, both with reference to God and to each other . . . because it is by his gift that we are one with each other; with him we are one spirit (1 Cor. 6:17), because our
21. Trin. 6.1.2; Hill, Trinity, 206.