19 For in him all the fullness of God was pleased to dwell, 20 and through him to reconcile to himself all things, whether on earth or in heaven, making peace by the blood of his cross. 
A great war ended in one death. Indeed, the war that should have resulted in the extinction of all humanity. So great was the rebellion of man that the wrath of God against all injustice should have been exercised against the creatures who rejected His majesty. The depth of brokenness in man has set man against God. So small a creature, incapable of even the most simple of tasks. Mankind cannot even raise itself to do one thing that is truly good. Man is so completely depraved that we will shake our fists in the face of the God who created us while simultaneously refusing to acknowledge that He exists. Yet, God considers these insignificant creatures worthy of salvation.
Jesus, the Christ, is God made flesh. He came to earth from heaven and lived a perfectly righteous life. Then He surrendered His life to the hands of the creatures that He made and submitted to death. In His death, He took upon Himself the wickedness of all who believe in Him. Jesus willingly carried a cross and offered Himself up as the recipient of God’s justice on our behalf. You have only to trust in Him for salvation.
Through Jesus, God brought peace to the souls of mankind. Further, God ended the war that was waged so long ago and restored Sabbath rest in Jesus. Life is in the blood. In Jesus’ death, we find life. His blood was poured out that you may live. Trust His atoning work and be saved.
Take note of a few details. First, Jesus is the agent of reconciliation. In the same way that Jesus is the agent of creation. He is also the sole means of re-creation. That is to say, He is the ONE by which salvation is accomplished. There is no other way to be at peace with God. Jesus is the only one. Second, His atoning work is so great that it reconciles “all things.” Consider that for a moment. All things are reconciled to God through Jesus Christ. God has determined that He will bring peace to all creation through Jesus’ atonement. ALL CREATION. He brings reconciliation to “all things, whether on earth or in heaven.” Creation was broken and separated from the love and mercy of God. That changes in Jesus. Now Sabbath rest is restored in Jesus… for all creation. Third, this reconciliation only comes through Jesus’ blood offered in sacrifice on our behalf. A death was required and God met the requirement for you. Whereas it was appropriate to slaughter mankind in order to sustain wrath and justice, God saw fit to sacrifice Jesus in your place.