A very strong proof of this destruction of death and its conquest by the cross is supplied by a present fact, namely this. All the disciples of Christ despise death; they take the offensive against it and, instead of fearing it, by the sign of the cross and by faith in Christ trample on it as on something dead. Before the divine sojourn of the Saviour, even the holiest of men were afraid of death, and mourned the dead as those who perish. But now that the Saviour has raised His body, death is no longer terrible, but all those who believe in Christ tread it underfoot as nothing, and prefer to die rather than to deny their faith in Christ, knowing full well that when they die they do not perish, but live indeed, and become incorruptible through the resurrection…. There is proof of this too; for men who, before they believe in Christ, think death horrible and are afraid of it, once they are converted despise it so completely that they go eagerly to meet it, and themselves become witnesses of the Saviour’s resurrection from it.
Dead men cannot take affective action; their power of influence on others lasts only till the grave. Deeds and actions that energise others belong only to the living. Well, then, look at the facts in this case. The Saviour is working mightily among men, every day He is invisibly persuading numbers of people all over the world, both within and beyond the Greek-speaking world, to accept His faith and be obedient to His teaching. Can anyone, in face of this, still doubt that He has risen and lives, or rather that He is Himself the Life? Does a dead man prick the consciences of men, so that they will throw all the traditions of their fathers to the winds and bow down before the teachings of Christ? If He is no longer active in the world, as He must needs be is He is dead, how is it that He makes the living to cease from their activities, the adulterer from his adultery, the murderer from murdering, the unjust from avarice, while the profane and godless man becomes religious? If He did not rise, but is still dead, how is it that He routs and persecutes and overthrows the false gods, whom unbelievers think to be alive, and the evil spirits whom they worship? For where Christ is named, idolatry is destroyed and the fraud of evil spirits is exposed; indeed, no such spirit can endure that Name, but takes to flight on sound of it. This is the work of One Who lives, not of one dead; and, more than that, it is the work of God.
Athanasius (296-373), On the Incarnation, 57, 60-61.