John 21:20-23 - Peter And The Other Disciple Jesus Loved
20 Peter turned round and saw that the favourite disciple of Jesus was following, the disciple who had leant on his breast at supper and put the question, "Lord, who is to betray you?" 21 So, on catching sight of him, Peter said to Jesus, "And what about him, Lord?"
22 Jesus replied, "If I choose that he should survive till I come back, what does that matter to you? Follow me yourself."
23 This started the report among the brotherhood that the said disciple was not to die. Jesus, however, did not say he was not to die; what he said was, "If I choose that he should survive till I come back, what does that matter to you?"