Verily, verily, I say unto you, When you were young, you dressed yourself, and walked where you would: but when you shall be old, you shall stretch forth your hands, and another shall dress you, and carry you where you would not.
All Commentaries on John 21:18 Go To John 21
John Chrysostom
AD 407
Our Lord having made Peter declare his love, informs him of his future martyrdom; an intimation to us how we should love: Verily, verily, I say to you, When you were young, you girded yourself, and walked where you would. He reminds him of his former life, because, whereas in worldly matters a young man has powers, an old man none; in spiritual things, on the contrary, virtue is brighter, manliness stronger, in old age; age is no hindrance to grace. Peter had all along desired to share Christ’s dangers; so Christ tells him, Be of good cheer; I will fulfill your desire in such a way, that what you has not suffered when young, you shall suffer when old: But when you are old. Whence it appears, that he was then neither ayoung nor an old man, but in the prime of life.
He says, Where you would not, with reference to the natural reluctance of the soul to be separated from the body; an instinct implanted by God to prevent men putting an end to themselves. Then raising the subject, the Evangelist says, This spoke He, signifying by what death he should glorify God: not, should die: he expresses himself so, to intimate that to suffer for Christ was the glory of the sufferer. But unless the mind is persuaded that He is very God, the sight of Him can in no way enableus to endure death. Wherefore the death of the saints is certainty of divine glory.