John 21:18-19; Psalm 18:2
The Lord said to Peter: When thou wast younger, thou didst gird thyself, and didst walk where thou wouldst: but when thou shalt be old, thou shalt stretch forth thy hands, and another shall gird thee, and lead thee whither thou wouldst not: and this He said, signifying by what death he should glorify God. Ps. The heavens show forth the glory of God: and the firmament declareth the works of His hands. Glory be to the Father.
Haydock
John 21
Verse 18. Thou shalt stretch forth thy hands … signifying by what death he should glorify God; that is, that a cross should be the instrument of his death and martyrdom. — Whither thou wouldst not: which is no more than to say, that a violent death is against the natural inclination of any man, even though he be ever so willing, and disposed to undergo it. Wi. — By this is meant the martyrdom of S. Peter, which took place thirty-four years after this. He was first cast into prison, and then led out to punishment as Christ had foretold him. He stretched out his arms to be chained, and again he stretched them out, when he was crucified; for he died on the cross, as the ancients assure us. Calmet.
Psalm 18
Verse 2. Firmament. Heb. “expansion,” or region of the stars, far above our atmosphere. Bert. — These two sentences express the same idea, unless the former may denote what we behold, and the firmament be explained of the higher heavens, (H.) where we imagine the throne of God to be placed. Some have taken these expressions in a gross sense, and asserted that the heavens are animated. Job xxxviii. 7. But we must allow that they are figurative expressions, which seem to give a soul to plants, stars, &c. C. — The beautiful works of God extort our admiration. H. — The silence of heaven speaks louder than any trumpet. S. Chrys. — “Who can behold the heavens, and yet be so foolish as not to acknowledge that a God exists? said Cicero, (H.) a learned pagan; (Arusp. and Nat. Deo. 2. C.) though they cannot determine of what nature the Deity may be. Leg. i. M. — Hands. Chal. “Those who look up at the heavens, publish the glory of the Lord; and those who raise their eyes towards the air, announce his works.” C. — The silent works declare God’s Majesty to those who consider them, and his preachers make the same known to their hearers by word of mouth. W. — S. Paul reproaches the philosophers of paganism for not understanding the language of the creation. Rom. i. 20. Job xii. 7. H. — The Church, which is so often styled the kingdom of heaven, makes God known, not only as a Creator, but also as a Redeemer. The figure is here most beautifully preserved. Heaven denotes the Church, as the stars represent apostolic men, who cease not to perform their duties day or night, in happier days as well as under persecution. Jesus Christ is the true sun of justice, enlightening every man that cometh into the world. S. Jo. i. — The Fathers have made these remarks. Bert. — What a consolation must it be for Catholics to think that the true doctrine will never cease, no more than the succession of day and night! We have received our creed, our orders and mission, from the apostles. The chain of succession has never been broken. Unhappy those who make a religion of their own to damn souls! who run, though God send them not! H.
Catena Aurea
18. Verily, verily, I say unto thee, When thou wast young, thou girdedst thyself, and walkedst whither thou wouldest: but when thou shalt be old, thou shalt stretch forth thy hands, and another shall gird thee, and carry thee whither thou wouldest not. 19. This spake he, signifying by what death he should glorify God.
CHRYSOSTOM. (Hom. lxxxvii) 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 unto thee, When thou wast young, thou girdedst thyself, and walkedst whither thou wouldest. 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 fulfil thy desire in such a way, that what thou hast not suffered when young, thou shalt suffer when old: But when thou art old. Whence it appears, that he was then neither a young nor an old man, but in the prime of life.
ORIGEN. (super. Matt.) It is not easy to find any ready to pass at once from this life; and so he says to Peter, When thou art old, thou shalt stretch forth thy hand.
AUGUSTINE. (Tract. cxxiii. 5) That is, shalt be crucified. And to come to this end, Another shall gird thee, and carry thee whither thou wouldest not. First He said what would come to pass, secondly, how it would come to pass. For it was not when crucified, but when about to be crucified, that he was led whither he would not. He wished to be released from the body, and be with Christ; but, if it were possible, he wished to attain to eternal life without the pains of death: to which he went against his will, but conquered by the force of his will, and triumphing over the human feeling, so natural a one, that even old age could not deprive Peter of it. But whatever be the pain of death, it ought to be conquered by the strength of love for Him, Who being our life, voluntarily also underwent death for us. For if there is no pain in death, or very little, the glory of martyrdom would not be great.
CHRYSOSTOM. (Hom. lxxxviii) He says, Whither thou wouldest 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 spake 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. (non occ.). But unless the mind is persuaded that He is very God, the sight of Him can in no way enable us to endure death. Wherefore the death of the saints is certainty of divine glory.
AUGUSTINE. (Tract. cxxiii) He who denied and loved, died in perfect love for Him, for Whom he had promised to die with wrong haste. It was necessary that Christ should first die for Peter’s salvation, and then Peter die for Christ’s Gospel.