The Resurrection of our Lord Jesus Christ is the new life of believers in Jesus; and this is the mystery of His Passion and Resurrection, which you ought well to know and to carry out in act. For not without a cause did Life come to death. Not without a cause did the Fountain of life, whence we drink in order that we may live, drink His cup which He was not bound to drink. For death was not Christ’s due portion. As to the question whence death has come, let us look to our origin. Sin is death’s parent. Had there been no sin, no one would have died. The first man received God’s law, that is, God’s commandment, on condition, that if he kept it he should live, if he violated it he should die. By not believing that he would die, he did what caused him to die; and found that to have been true which the Giver of the law had affirmed. Thence came death, thence man became mortal, thence came labour, thence misery, thence the second death after the first, that is, after temporal death, death everlasting. This tradition of death, this law of destruction, binds every man who is born, except that one Man who became Man that man should not perish.

For He came bound by no law of death; therefore He is called in the Psalm, “Free among the dead;” whom in all purity a Virgin conceived; whom she as a Virgin bore, and remained a Virgin; who lived without sin, who did not die because of sin; sharing in our penalty, not in our offence. Death is the penalty of offence; our Lord Jesus Christ came to die, did not come to sin; by sharing in our penalty without our offence, He annulled both our offence and penalty. What penalty? That which was due to us after this life. So He was crucified, that on the Cross He might show the dying-out of our old man; and He rose, that in His own life He might show our new life.

[St. Augustine of Hippo, Sermon CCXXXI] 

“Verily verily I say unto you, the hour is coming and now is, when the dead shall hear the Voice of the Son of God; the hour again that is, when they that hear shall live.” (John 5:25)

“By the words then in the beginning, He means the time of the resurrection, wherein He teaches through the word of the Judge that they that sleep shall rise again to answer for their life in the world, that as I said before, devising the fear thence arising as a bridle, He might persuade them to live full excellently and wisely: by the closing words He shews that the due time of believing is now come, but also says that everlasting life will be the reward of obedience: all but declaring, Ye shall all come to judgement, sirs, that is at the time of the Resurrection, but if it seem bitter to you to be punished, and to undergo endless penalties at the hand of the offended Judge, suffer not the time of obedience to pass by, but laying hold of it while yet present, haste ye to attain to everlasting life.”

[St. Cyril the Pillar of Faith, Commentary on the Gospel of St. John]