JMNT(i)
21 Peter, therefore, seeing and perceiving this one, says to Jesus, "Lord (Master), now what [of] this man?"
22 Jesus then says to him, "If I am intending (willing; purposing) him to continue remaining until I am progressively coming, what [is it; effect comes] toward you? As for you, you be habitually following Me!"
23 Then this word (saying; message; idea) went forth unto (or: into the midst of) the brothers (= fellow believers; members of the group) – that that disciple continues not dying off. Yet Jesus did not say to him that he continues not dying off, but rather, "If I am intending (willing; purposing) him to continue remaining until I am progressively coming, what [is it; effect comes] toward you?"
24 This is the disciple: even the one constantly witnessing and testifying about these things, even the one writing these things – and we have seen and know that his witness (testimony) is true (genuine; real).