John 21:20-23 - Peter And The Other Disciple Jesus Loved
20 Peter turned and saw following them the disciple whom Jesus specially loved, who at the supper leaned back upon Jesus' breast and asked, "Lord, who is it that is going to betray you?" 21 So when Peter saw him, he said to Jesus, "But, Lord, what about him?"
22 Jesus answered him, "If I wish him to wait until I come, what is that to you? You must keep on following me."
23 So the report got out among the brothers that this disciple was not going to die. But Jesus did not tell him that he was not going to die; He said only, "If I wish him to wait until I come, what is that to you?"