16 He saith to him again: Simon, son of John, lovest thou me? He saith to him: Yea, Lord, thou knowest that I love thee. He saith to him: Feed my lambs. 17 He said to him the third time: Simon, son of John, lovest thou me? Peter was grieved, because he had said to him the third time: Lovest thou me? And he said to him: Lord, thou knowest all things: thou knowest that I love thee. He said to him: Feed my sheep.
Chrysostom: Three confessions are made to answer to the three denials; that the tongue might show as much love as it had fear.
Theophylact: Thence is taken the custom of threefold confession in baptism.
Alcuin: To feed the sheep is to support the believers in Christ from falling from the faith, to provide earthly sustenance for those under us, to preach and exemplify withal our preaching by our lives, to resist adversaries, to correct wanderers.
Theophylact: There is a difference perhaps between lambs and sheep. The lambs are those just initiated, the sheep are the perfected.
Augustine: They who feed Christ’s sheep, as if they were their own, not Christ’s, show plainly that they love themselves, not Christ; that they are moved by lust of glory, power, gain, not by the love of obeying, ministering, pleasing God.
Unfaithful servants arose, who divided Christ’s flock, and handed down the division to their successors: and you hear them say, Those sheep are mine, what seekest thou with my sheep, I will not let thee come to my sheep. If we call our sheep ours, as they call them theirs, Christ hath lost His sheep.
Scripture from the Douay-Rheims Bible. Commentary from St. Thomas Aquinas, Catena Aurea, Vol. IV (London: Rivington, 1845).