While it is clear that the cross is the telos of the life of Christ, Athanasius’ understanding of the Fall, the “death” that now permeates human life and society, seems to suggest that the incarnation itself is the beginning of the death of Christ.
He says: “Thus, taking a body like our own, because all our bodies were liable to the corruption of death, he surrendered His body to death in place of all, and offered it to the Father… This He did that He might turn again to incorruption men who had turned back to corruption, and make them alive through death by the appropriation of His body and by the grace of His resurrection… For the solidarity of mankind is such that, by virtue of the Word’s indwelling in a single human body, the corruption which goes with death has lost its power. (2.8-9)”
To be sure, all through this section Athanasius is also talking about Christ’s actual death on the cross, but I’ve just highlighted several of the places where he seems to almost conflate the incarnation and the cross. This would seem to have some implications for some of the current discussions regarding the imputation of Christ’s active and passive obedience. Here we have at least one formulation which seems content to see no dichotomy between the two.