Jesus Predicts Peter’s Martyrdom

God in His Word often uses metaphors in order to help us grasp the nature of things and to instruct us in how we should live. Some of the most common metaphors He uses to describe His people employ imagery related to sheep, lambs, and flocks (Ps. 23; Isa. 40:11; John 10:1–18). Jesus used this same imagery when He restored Peter to service, telling the Apostle to tend His sheep (John 21:15–17).

John Calvin comments on the significance of such imagery, noting the mildness of sheep and their need of a shepherd’s guidance as the point of comparison between us as followers of the Lord and sheep. He writes, “None can be fed to salvation by the doctrine of the Gospel but those who are mild and teachable; for it is not without reason that Christ compares his disciples to lambs and sheep.” We must admit that we are lost apart from the Lord’s shepherding, just as sheep are lost without a shepherd. This is true not only of laypeople in the church but also of the church’s leaders. And it was true even of the Apostles. As we see in today’s passage, Peter was likewise entreated by our Savior to follow Him (John 21:19). Peter and the other Apostles had to humble themselves like sheep and follow Jesus no less than the rest of us do.

Today’s passage also indicates that Jesus, during His restoration of Peter, told the Apostle the kind of death he would experience (v. 19). When Peter reached old age, Jesus said, he would stretch out his hands and be led to where he did not want to go (v. 18). The phrase “stretch out your hands” was a common way of alluding to crucifixion in the ancient world, so we see here a prediction that Peter would eventually be martyred by means of crucifixion. Later tradition holds that Peter was crucified upside down during the reign of Nero sometime in the early to mid-60s AD. While it is possible that Peter was not crucified upside down, it is certain that he was crucified given the evidence that we have both from texts such as John 21:18 and from extrabiblical documents.

We therefore have a clear picture of how the grace of God changed Peter. Simon Peter went from a man who so feared arrest and crucifixion that he denied knowing Christ to one who would follow our Lord literally to the cross (John 18:15–27; 21:18–19). Jesus strengthened Peter and enabled him to stand for Him even when it meant the loss of his own life. May our gracious Savior do the same for us.