For it pleased the Father that in Him should all fulness dwell;
And, having made peace through the blood of His cross, by Him to reconcile all things unto Himself; by Him, I say, whether they be things in earth, or things in heaven.
The Father was satisfied that in Jesus Christ all the fullness of God, Himself, would dwell.
The word fullness is translated from the Greek pleroma, and was really just another way to say that Jesus is truly God. I have always been taught that Jesus was wholly God, and wholly man, which is why He alone could be the ultimate sacrifice for sin. Sinless, His blood was not touched with corruption; human, He could die. Wholly God, He could defeat death; wholly man, He could give Himself to atone for all sin.
Dwell in this passage denotes a permanent condition, not a temporary one. Jesus didn’t become God for a short time. He never wasn’t God. Before time, and for all eternity, Jesus Christ is God.
“Thus the phrase in Him should all the fullness dwell gathers into a grand climax the previous statements – image of God, first-born of all creation, Creator, the eternally preexistent, the Head of the Church, the victor over death, first in all things. On this summit we pause, looking like John, from Christ in His fullness of deity to the exhibition of that divine fullness in redemption consummated in heaven.”Vincent, Blue Letter Bible
I think it is important here that we understand that, yes, it was the shedding of blood that reconciles man to God, when man accepts the death and resurrection of Jesus Christ as his only route to heaven.
Jesus’ actual blood was not a magic potion that absolves us of sin. If that were so, anyone who had been spattered with His blood at any point on that awful day would instantly be free from the results of sin. If it were so, someone would surely, by now, have figured out a way to “perpetuate” His blood and sell it for the “salvation” of anyone who could afford to buy it.
The blood of the cross speaks to us of the real, physical death of Jesus Christ in our place, on our behalf, before God. That literal death in our place, and the literal judgment He bore on our behalf, is what saves us.Guzik, Blue Letter Bible