In reading a retelling of Josephus' account of the fall of Jerusalem, I came across something first hand that I've been looking for since I heard it from Ray VanderLaan first, years ago.
Over the Golden Gate of the temple, going from the court into the temple itself, was a celebrated golden vine. Josephus: "Like a true natural vine, it grew gater and greater; men would be offering gold, some to make a leaf; some, a grape; some, a bunch; and these were hung upon it, and so it was in reign continually."
Now consider John 14-17 in this context. The last verse of John 14, Jesus says, "Rise, let us go from here," meaning from the upper room. In 18:1, He goes out and crosses the Kidron to Gethsemane.
So where was Jesus while speaking John 15-17? I would submit that He was in the temple.
Standing before the golden temple vine, which Israelites enlarged with their offerings, Jesus used it as a type to point to Himself. HE is the real vine, and it will grow and bear fruit as we stay in HIM. Not in the temple, but in Jesus.
He speaks of another helper who will come, and when He comes at Pentecost they are in the temple. The Spirit dwells in us, the new temple of God.
He prays a great high priestly prayer. Where do priests pray? In the temple.
His prayer for unity, that the world may know God, parallels Solomon's prayer at the dedication of the temple. The church is a temple being built (Ephesians 2:21).
Then He goes out to be pressed in the olive press of Gethsemane, complete with sweat like drops of blood. The vine is giving forth juice/wine/blood already.
The historical context of Scripture really makes the Word sing, harmonizing beautifully with itself.