In John 13–16, Jesus speaks on a variety of topics to his disciples. He talks about humility, servanthood, a coming betrayal, the commandment of love, going to the Father, revealing the Father, the promise of answered prayer, sending the Holy Spirit for indwelling, peace, abiding in the vine, loving one another, persecution from the world, the role of the Holy Spirit in the world and in disciples, the sorrow at the crucifixion, the joy at the resurrection, and praying in Jesus’ name.
More topics can probably be added to that list. But, for all the subjects Jesus teaches on, he summarizes the core message of the Farewell Discourse in John 16:28, one of the last few verses of John 13–16:
“I came from the Father and entered the world; now I am leaving the world and going back to the Father.”
The verse can be arranged this way to portray its artistry:
A I came from the Father
B and entered the world;
B’ now I am leaving the world
A’ and going back to the Father
In John 16:28, Jesus explicitly says what he has been teaching the disciples. It is a teaching that captures the truth of both his origin and destination.
This verse also shows that understanding why Jesus came into the world must incorporate an understanding of the Father’s role.
Of all the correct statements that can be said about Jesus, John 16:28 is surely one of the most fundamental. If John 16:28 is denied, Jesus is denied.