And the Glory which You gave Me I have given them, that they may be one just as We are One: I in them and You in Me; that they may be made perfect in one and that the world may know that You have sent Me, and have loved them as You have loved Me.
This "oneness" is the perfect unity given by God... our unity with Them and with each other... the physical unity that people seem to be looking for will NEVER HAPPEN.
He isn't talking about your body or your soul. He's talking about the REAL you... your spirit being that you are since you became born again.
2 Corinthians 5:17 tells us that we are a brand new creature in Christ Jesus... old things are passed away and all things have become new.
We are now a brand new spirit... and because we are spirit, we have God the Father Who is Spirit, Jesus Who is both Spirit and flesh, and the Holy Spirit all living within our spirit.
Reverend Robert W. & Mary C. Butler