We’ve seen that for Augustine the human condition is pretty dire. Humans, due to the sin of our first parents, find ourselves spiritually crippled and condemned to death, our wills utterly impotent on their own to change our situation. A rather grim situation.
But of course, the Christian story is the story of God’s mighty acts to save his people. In chapter 10 Augustine considers the work of Christ. He notes that “the human race was bound in a just doom and all men were children of wrath.” Interestingly, “wrath” here seems to mean more than just the prospect of punishment at some future time. He quotes John’s Jesus to the effect that “he that believes not does not have life. Instead, the wrath of God abides in him.” Wrath is a state men are in, indeed born into. We might say that our sinful nature is what makes us liable to God’s verdict, or “wrath.”
To turn away wrath, then, there was need for a Mediator. Augustine doesn’t go into detail about how Christ saves us, he simply says that “a Reconciler who by offering a unique sacrifice, of which all the sacrifices of the Law and Prophets were shadows, should allay that wrath.”
There’s a longstanding debate between Catholics and Protestants over whether justification is a verdict whereby God declares us innocent on account of Christ’s sacrifice, or on account of an actual change in us worked by grace. At least here Augustine can seem to take both views. He says that Christ’s sacrifice allays wrath, but also says that “we are reconciled to God through the Mediator and receive the Holy Spirit so that we may be changed from enemeis into sons….” This would seem to suggest that we become sons by the Holy Spirit working some actual change in us. We’ll come back to justification in a later chapter, so things may be cleared up a bit there.
Augustine spends the rest of chapter 10 discussing the two natures of Christ. He is careful to assert that it is a complete human nature which is united to the divine Word, not simply a body which has the Word as its soul. He also denies what would come to be called “subordinationism,” the view that there is inequality between the persons of the Trinity:
Accordingly, in so far as he is God, he and the Father are one. Yet in so far as he is man, the Father is greater than he. Since he was God’s only Son — not by grace but by nature — to the end that he might indeed be the fullness of all grace, he was also made Son of Man — and yet he was in the one nature as well as in the other, one Christ.
In Chapter 11 Augustine goes on to discuss the Incarnation as “the Prime Example of the Action of God’s Grace.” Human nature didn’t merit to be united to Godhead, it was an act of sheer grace on God’s part. And Jeus was God’s Son from the very beginning of his existence – there is no hint of Adoptionism here. “Indeed it was Truth himself, God’s only begotten Son — and, again, this not by grace but by nature — who, by grace, assumed human nature into such a personal unity that he himself became the Son of Man as well.” Note here the reversal of the Son of Man/Son of God distinction characteristic of the Fathers; in the Bible the “Son of Man” can be a semi-divine eschatological figure, whereas many humans (such as David) can be referred to as a “son of God.” The Fathers, however, tend to reverse this usage and use “Son of Man” to Jesus considered in his human nature, and “Son of God” according to his divine nature. The point, though, is that the Son of God is the Son by nature, but he takes human nature to himself by grace.
And this graceful uniting of the human and divine natures is the work of the Spirit: “This same Jesus Christ, God’s only Son our Lord, was born of the Holy Spirit and the Virgin Mary. Now obviously the Holy Spirit is God’s gift, a gift that is itself equal to the Giver; wherefore the Holy Spirit is God also, not inferior to the Father and the Son.” The same Spirit which overshadowed Mary also calls us out of our sin and changes us from enemies to sons of God.