John 21:19-21

Now He said this to indicate the kind of death by which Peter would glorify God. And after saying this, He said to him, “Follow Me [walk the same path of life that I have walked]!” Peter turned and saw the disciple whom Jesus loved following them; the one who also had leaned back on His chest at the supper and had said, “Lord, who is it that is going to betray You?” So when Peter saw him, he asked Jesus, “Lord, and what about this man [what is in his future]?”