It's good that Jesus went away
The disciples were still too preoccupied to take seriously the meaning of Jesus going away (5). Peter had already asked him, “Where are you going?” but only superficially (13:36) – he and all the disciples were far more concerned about the personal loss to them of Jesus leaving (6). Grief stopped them considering the meaning of his going but in fact his going away would provide the answer to their sadness.
.
Jesus then told them emphatically that his leaving was good news, because his going would result in the coming of “the Counsellor”, the Holy Spirit (7; 14:16-17; 14:26; 15:26). It was not that Jesus and the Spirit could not both be present together, for the Spirit was already at work in the ministry of Jesus (1:32; Acts 10:38). But the basis of the Spirit’s ministry throughout the world would be the death and resurrection of Jesus (7:39).
.
So it was necessary for Jesus to go away, in order that his mission through the disciples could be carried forward. This would also be for their personal benefit, for the Spirit is not bounded by a human body as Jesus was, and so he is able to be with all Christians, wherever in the world they may be, as “another Helper” like Jesus himself (14:16).