Christ's death has undone our death

This post continues a series in the book Life in the Trinity by Donald Fairbairn. For other posts in the series, click a number: 1234578.

Fairbairn addresses the related topics of  redemption and immortality, citing the patristic fathers who, "wrote of the death of Christ in terms of its undoing our death" (p163). As noted by the fathers, by virtue of the fall (Adam's transgression), we humans are mortal, that is, subject to death (corruption). However, God created us for immortality - our "share by grace in the natural immortality that characterizes the persons of the Trinity." (p163) How can what was lost be restored? Note comments from Athanasius:
What should God have done? Demand repentance from men for the transgression? For one might say that this was fitting for God, that as [humans] had become subject to corruption by the transgression, so by repentance they might return to incorruption. But repentance would not have saved God's honour, for he would still have remained untruthful unless men were in the power of death. Repentance gives no exemption from the consequences of nature, but merely looses sins. If, therefore, there had been only sin and not its consequence of corruption, repentance would have been very well. But if, since transgression had overtaken them, men were now prisoners to natural corruption, and they had been deprived of the grace of being in the image [of God], what else should have happened? Or who was needed for such grace and recalling except the Word of God, who also in the beginning had created the universe from nothing?... For since he is the Word from the Father and above everyone, consequently he alone was both able to recreate the universe and be worthy to suffer for all and to be an advocate on behalf of all before the Father. (On the Incarnation, par. 7; cited by Fairbairn on p164)
Jesus, through his vicarious humanity, has recreated us in God's image, thereby undoing our death (corruption). As Fairbairn notes, "death died with the death of Christ, and we who were in slavery to death have now been set free... Christ's death [is]... both a sacrifice to remove wrath/guilt and.. a victory over the demonic powers that hold us captive to death" (p165 and note Col 2:13-15 and Hebrews 2:14-17).

On this point, Fairbairn also quotes Cyril of Alexandria:
[Jesus] was scourged unjustly, that he might deliver us from merited chastisement; he was buffeted and smitten that we might buffet Satan, who had buffeted us, and that we might escape from the sin that cleaves to us through the original transgression. For if we think aright, we shall believe that all Christ's sufferings were for us and on our behalf and have power to release and deliver us from all those calamities we have deserved for our revolt from God. For as Christ, who knew not death, when he gave up his own body for our salvation, was able to loose the bonds of death for all mankind, for he, being One, died for all. (Commentary on John, book 12, introduction; cited by Fairbairn on p166)
Fairbairn then makes this important statement about Christ's representative/ substitutionary death:
What Scripture compels us to say, and what the early church recognized, is that somehow God the Son died for us... We turned away from God. We lost the share in the fellowship between the Father and the Son that God had given us at creation. We are born spiritually dead, enslaved to death and the devil, and unable to return to God. How can this terrible situation be remedied? By an atoning sacrifice. The consequence of sin is death, which implies both physical separation of the soul from the body and, more significantly, alienation from God. So if human beings are to be restored to life, then a substitute must be brought forth who can take that alienation away from us by taking it upon himself. 
The entire Old Testament sacrificial system testifies to the necessity of such a sacrifice, and the repetition of the Old Testament sacrifices shows that they do not provide that sacrifice; they merely symbolized it. So who or what could be this sacrifice? It had to be a human being, since only a human would qualify to die in place of other men and women. He had to be a sinless human being, one who had never lost his share in the love between the Father and the Son, since a sinful human being could die for his own sin, but not for someone else's. And he had to be able to die not just for one other person's sin but for the sin of many people at once, indeed for the sin of the world. Thus he had to be somehow an infinite human being, whose life would be of such infinite value that it could be laid down for the sin of the world rather than just for the sin of one or two other people. 
Who then qualifies to offer such a sacrifice? Who is fully human and utterly sinless and yet also infinite? Only the incarnate Word, God the Son after he has become a man.  And this, John says, is the one whom God sent specifically to offer the atoning sacrifice. (pp166-167, and see 1John 4:7-12 and Romans 5).
Fairbairn concludes by noting that Jesus' resurrection reverses our death.  His resurrection in his own human (physical) body "undoes our physical death, serving as a seal that we too shall one day be physically resurrected from the dead..." (p180, emphasis added). In like manner, his resurrection reverses our spiritual death. In his humanity, Jesus died a sinner, bearing on the cross our sin. But in his resurrection, Jesus, in his humanity, is restored to full fellowship with God. This is symbolized by the image of Jesus sitting at "the right hand of God" in heaven. Cyril of Alexandria writes of this in noting that the Son takes up his former glory "in a way that befits a man." (Christ is One, cited by Fairbairn on p181)

Through the humanity of the Son of God, who died and rose for us and with us, death and Satan have been conquered. The fall has been reversed; humanity has been recreated; and as a consequence, human fellowship with the triune God, who alone is immortal, is restored. Thank you Jesus!