John 21:22
ESV - 22 Jesus said to him, "If it is my will that he remain until I come, what is that to you? You follow me!
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
John 22: Jesus answered, "If I want him to remain alive until I return what is that to you? Could it be that Christ meant he will meet again with John on the Island of Patmos? It was the Lord who in Revelation 1: 10 said to John, "Write on a scroll what you see......." was it not? John was in his 60's supposedly when that happened.