If, then, it is by the sign of the cross and by faith in Christ that death is trampled underfoot, it is clear that it is Christ Himself and none other Who is the Archvictor over death and has robbed it of its power. Death used to be strong and terrible, but now, since the sojourn of the Savior and the death and resurrection of His body, it is despised; and obviously it is by the very Christ Who mounted on the cross that it has been destroyed and vanquished finally. When the sun rises after the night and the whole world is lit up by it, nobody doubts that it is the sun which has thus shed its light everywhere and driven away the dark.
Equally clear is it, since this utter scorning and trampling down of death has ensued upon the Savior’s manifestation in the body and His death on the cross, that it is He Himself Who brought death to nought and daily raises monuments to His victory in His own disciples. How can you think otherwise, when you see men naturally weak hastening to death, unafraid at the prospect of corruption, fearless of the descent into Hades, even indeed with eager soul provoking it, not shrinking from tortures, but preferring thus to rush on death for Christ’s sake, rather than to remain in this present life? If you see with your own eyes men and women and children, even, thus welcoming death for the sake of Christ’s religion, how can you be so utterly silly and incredulous and maimed in your mind as not to realize that Christ, to Whom these all bear witness, Himself gives the victory to each, making death completely powerless for those who hold His faith and bear the sign of the cross?
No one in his senses doubts that a snake is dead when he sees it trampled underfoot, especially when he knows how savage it used to be; nor, if he sees boys making fun of a lion, does he doubt that the brute is either dead or completely bereft of strength. These things can be seen with our own eyes, and it is the same with the conquest of death. Doubt no longer, then, when you see death mocked and scorned by those who believe in Christ, that by Christ death was destroyed, and the corruption that goes with it resolved and brought to end.
-Athanasius, On the Incarnation of the Word
Athanasius of Alexandria (c. 296 – 373 AD) was a bishop of the church and one of the most important theologians of the early centuries. His defense of the Trinity against Arianism led to numerous exiles and help sway the church back in the direction of orthodoxy.