5 But first the Lord asks what He knew, and that not once, but a second and a third time, whether Peter loved Him; and just as often He has the same answer, that He is loved, while just as often He gives Peter the same charge to feed His sheep. To the threefold denial there is now appended a threefold confession, that his tongue may not yield a feebler service to love than to fear, and imminent death may not appear to have elicited more from the lips than present life.
Let it be the office of love to feed the Lord's flock, if it was the signal of fear to deny the Shepherd. Those who have this purpose in feeding the flock of Christ, that they may have them as their own, and not as Christ's, are convicted of loving themselves, and not Christ, from the desire either of boasting, or wielding power, or acquiring gain, and not from the love of obeying, serving, and pleasing God. Against such, therefore, there stands as a wakeful sentinel this thrice inculcated utterance of Christ, of whom the apostle complains that they seek their own, not the things that are Jesus Christ's. For what else mean the words, “Do you love me?
Feed my sheep,” than if it were said, If you love me, think not of feeding yourself, but feed my sheep as mine, and not as your own; seek my glory in them, and not your own; my dominion, and not yours; my gain, and not yours; lest you be found in the fellowship of those who belong to the perilous times, lovers of their own selves, and all else that is joined on to this beginning of evils? For the apostle, after saying, “For men shall be lovers of their own selves,” proceeded to add, “Lovers of money, boastful, proud, blasphemers, disobedient to parents, unthankful, wicked, irreligious, without affection, false accusers, incontinent, implacable, with out kindness, traitors, heady, blinded; lovers of pleasures more than of God; having a form of godliness, but denying the power thereof.” All these evils flow from that as their fountain which he stated first, “lovers of their own selves.”
With great propriety, therefore, is Peter addressed, “Do you love me?” and found replying, “I love You:” and the command applied to him, “Feed my lambs,” and this a second and a third time. We have it also demonstrated here that love and liking are one and the same thing; for the Lord also in the last question said not Diligis me? But, Amas me? Let us, then, love not ourselves, but Him; and in feeding His sheep, let us be seeking the things which are His, not the things which are our own.
For in some inexplicable way, I know not what, every one that loves himself, and not God, loves not himself; and whoever loves God, and not himself, he it is that loves himself. For he that cannot live by himself will certainly die by loving himself; he therefore loves not himself who loves himself to his own loss of life. But when He is loved by whom life is preserved, a man by not loving himself only loves the more, when it is for this reason that he loves not himself [namely] that he may love Him by whom he lives.
Let not those, then, who feed Christ's sheep be “lovers of their own selves,” lest they feed them as if they were their own, and not His, and wish to make their own gain of them, as “lovers of money;” or to domineer over them, as “boastful;” or to glory in the honors which they receive at their hands, as “proud;” or to go the length even of originating heresies, as “blasphemers;” and not to give place to the holy fathers, as those who are “disobedient to parents;” and to render evil for good to those who wish to correct them, because unwilling to let them perish, as “unthankful;” to slay their own souls and those of others, as “wicked;” to outrage the motherly bowels of the Church, as “irreligious;” to have no sympathy with the weak, as those who are “without affection;” to attempt to traduce the character of the saints, as “false accusers;” to give loose reins to the basest lusts, as “incontinent;” to make lawsuits their practice, as “implacable;” to know nothing of loving service, as those who are “without kindness;” to make known to the enemies of the godly what they are well aware ought to be kept secret, as “traitors;” to disturb human modesty by shameless discussions, as “heady;” to understand neither what they say nor whereof they affirm, as “blinded;” and to prefer carnal delights to spiritual joys, as those who are “lovers of pleasures more than lovers of God.” For these and such like vices, whether all of them meet in a single individual, or whether some dominate in one and others in another, spring up in some form or another from this one root, when men are “lovers of their own selves.” A vice which is specially to be guarded against by those who feed Christ's sheep, lest they be seeking their own, not the things that are Jesus Christ's, and be turning those to the use of their own lusts for whom the blood of Christ was shed. Whose love ought, in one who feeds His sheep, to grow up unto so great a spiritual fervor as to overcome even the natural fear of death, that makes us unwilling to die even when we wish to live with Christ. For the Apostle Paul also says that he had a desire to be dissolved, and to be with Christ, and yet he groans, being burdened, and wishes not to be unclothed, but clothed upon, that mortality may be swallowed up of life. And so to His present lover the Lord said, “When you shall be old, you shall stretch forth your hands, and another shall gird you, and carry you whither you would not. For this He said to him, signifying by what death he should glorify God.” “You shall stretch forth your hands,” He said; in other words, you shall be crucified. But that you may come to this, “another shall gird you, and carry you,” not whither you would, but “whither you would not.” He told him first what would happen, and then how it should come to pass. For it was not after being crucified, but when actually about to be crucified, that he was carried whither he would not; for after being crucified he went his way, not whither he would not, but rather whither he would. And though when set free from the body he wished to be with Christ, yet, were it only possible, he had a desire for eternal life apart from the grievousness of death, to which grievous experience he was unwillingly carried, but from it [when all was over] he was willingly carried away; unwillingly he came to it, but willingly he conquered it, and left this feeling of infirmity behind that makes every one unwilling to die—a feeling so permanently natural, that even old age itself was unable to set the blessed Peter free from its influence, even as it was said unto him, “When you shall be old,” you shall be led “whither you would not.” For our consolation the Saviour Himself transfigured also the same feeling in His own person when He said, “Father, if it be possible, let this cup pass from me;” and He certainly had come to die without having any necessity, but only the willingness to die, with power to lay down His life, and with power to take it again. But however great be the grievousness of death, it ought to be overcome by the power of that love which is felt to Him who, being our life, was willing to endure even death in our behalf. For if there were no grievousness, even of the smallest kind, in death, the glory of the martyrs would not be so great. But if the good Shepherd, who laid down His own life for His sheep, has raised up so many martyrs for Himself out of the very sheep, how much more ought those to contend to death for the truth, and even to blood against sin, who are entrusted by Him with the feeding, that is, with the teaching and governing of these very sheep? And on this account, along with the preceding example of His own passion, who can fail to see that the shepherds ought all the more to set themselves closely to imitate the Shepherd, if He was so imitated even by many of the sheep under whom, as the one Shepherd and in the one flock, the shepherds themselves are likewise sheep? For He made all those His sheep for [all of] whom He died, because He Himself also became a sheep that He might suffer for all.
Source: Tractates on the Gospel of John (New Advent)