John 16:28

I came out from the Father, and am come into the world: again, I leave the world and go unto the Father.

These words, as Jesus promised, are not dark sayings at all but the plainest possible statements of the profoundest facts in Christianity. The incarnation, the Godhead of Jesus, the passion, death, resurrection, and ascension are all included in this.

I leave the world ... The prophetic use of the present tense for the future here refers to his death, resurrection, and ascension.

And I go to the Father ... This also prophetically referred to the ascension and resumption by Christ of that glory he had with the Father before the world was.

I came forth from the Father ... This first clause marks Jesus' entry into our earth life as an act of his own volition. He decided to come, chose the time and place of entry, elected the particular race that would provide him a mortal body, and timed the entire sequence of events to fulfill the 333 prophecies of the Old Testament bearing upon the first advent of the Messiah. Likewise, his departure to be with the Father was revealed here as an act of his own volition.