John Calvin Commentary John 21:20

"Peter, turning about, seeth the disciple whom Jesus loved following; who also leaned back on his breast at the supper, and said, Lord, who is he that betrayeth thee?" — John 21:20 (ASV)

And Peter, turning about. In Peter, we have an example of our curiosity, which is not only superfluous but even hurtful when we are drawn away from our duty by looking at others. For it is almost natural for us to examine the way other people live instead of examining our own, and to try to find idle excuses in them. We willingly deceive ourselves with this semblance of an excuse—that other people are no better than we are—as if their indolence freed us from blame. Scarcely one person in a hundred considers the significance of those words of Paul,

Every man shall bear his own burden (Galatians 6:5).

In the person of one man, therefore, there is a general reproof of all who look around them in every direction to see how other men act, and pay no attention to the duties which God has enjoined on them. Above all, they are grievously mistaken in this respect: they neglect and overlook what is demanded by every man’s special calling.

Out of ten persons, it may happen that God will choose one to test him with heavy calamities or great labors, and He will permit the other nine to remain at ease or, at least, will test them lightly. Besides, God does not treat all in the same manner but tests everyone as He thinks fit. As there are various kinds of Christian warfare, let every man learn to keep his own station. Let us not inquire like busybodies about this or that person when the heavenly Captain addresses each of us, for we ought to be so submissive to His authority that we forget everything else.

Whom Jesus loved. This circumlocution was inserted to inform us of the reason Peter was led to ask the question related here. He thought it strange that he alone should be called and John overlooked, whom Christ had always loved so warmly. Peter, therefore, had some apparently good reason for asking why no mention was made of John, as if Christ’s disposition towards him had changed. Yet Christ cuts his curiosity short by telling him that he ought to obey God’s call and has no right to inquire what other people are doing.