But he that is joined unto the Lord is one spirit. (I Cor. 6:7)
This verse tells us HOW Jesus Christ dwells in us: He joins our human spirit to Himself – to His Spirit. This is CHRIST IN US.
The word translated, “joined,” could be translated, “glued,” or, “cemented.”
We are ONE with Jesus Christ through the union of our human spirit with His Spirit. This agrees with the pictures that God gives us of our spiritual union with Christ – baptized INTO Christ; baptized INTO the name of Christ; crucified WITH Christ; planted into the likeness of His death and resurrection; and of course, Christ in us, the hope of glory.
The spiritual union of our human spirit with Jesus Christ is the new creature in Christ Jesus. This is what is born through the new birth. It is the new man; the inner man.
Furthermore, it tells us how we have eternal life. Jesus Christ IS the resurrection and the life. Thus, when we are joined to Him, we are not joined to a THING called life, but joined to a Person who IS Life.
We are eternally alive because we are joined to the One who is the resurrection and the life.
God has given us all things freely IN HIS SON. And the saint is joined to Him. This is why, “we are complete in Him.” (Col. 2:9)