In St. Cyrill’s Commentary on John, he refers explicitly to the reason for Christ’s appearance to St. Thomas and to all the apostles in His resurrected human body. He writes:

St. Cyril of Alexandria

What need was there for the showing of His hands and side, if in accordance with the depravity of some, He did not rise with His own flesh? If He wanted His disciples to believe differently concerning Him, why did He not rather appear in a different frame, and by putting the form of the flesh to shame, draw them towards a different understanding? But it was most important that He show Himself carefully at that time so that they should believe in the future resurrection of the flesh; so important that even when the time seemed right to change the fashion of His body into ineffable and supranatural glory, He providentially deigned to appear once again as He was before, so that He should not be thought of as having any both than that in which He had even suffered death on the Cross. That the glory of the Holy Body could not have been borne by our eyes (if indeed Christ had wanted to reveal it before ascending to the Father), you will easily understand, when you consider the Transfiguration on the mount which was revealed to the holy disciples. For the blessed Evangelist Matthew writes that Jesus took Peter, James and John and went up to the mountain, and He was transfigured before them, and His face shone as lightning and His garments became white as snow, while they, unable to bear the vision, fell on their faces. Most prudently, then, our Lord Jesus Christ, not yet having transformed His Temple into its due and proper glory, still appeared in His original shape, wishing that the belief in the Resurrection should not be transferred to a shape or body other than that which He took from the Holy Virgin, and in which He was crucified and died according to the Scriptures; for the power of death extended only over the flesh, from which it had been set free.

The strong salvation perspective in Cyril’s Christology is more than apparent here. The underlying presupposition is clear enough: Christ could not truly be said to have redeemed mankind – human flesh, by which Cyril means human nature in its totality – unless He had also resurrected His own human body.

Christ, then, deigned to appear before His disciples still bearing the signs of corruptibility on His hands and side – marks which, properly speaking, should no longer have been present on His resurrected and therefore incorruptible body – so as to make it absolutely clear that He had risen with the very same body that He had received from the Holy Virgin Mary.