Colossians 1:15-20 exalts Christ for who He is. It shows that Christ is our creator. He made the world. He made people. He created the angelic or spiritual world in addition to the physical world. It is by the power of the eternal Christ that everything continues to exist and to operate.
In addition to being our creator, Christ is also our ruler. He is the head of the church. He is the source of the church. He is the leader of the church in every area, including the area of resurrection. Christ ultimately rules not only over the church, but also over all things.
Along with being creator and ruler, Christ is the great reconciler. He makes peace between God and men. He will one day restore this fallen creation to it's original glory. The cross of Christ was the means through which Christ made peace between sinful man and a holy God.
How should a knowledge of Christ's greatness impact our lives? First, we ought to worship the one who made us, rules over us, and gives us peace with God. Second, we should trust the one who holds this life together- the one who will restore the earth to it's former glory- the one died on our behalf. Trusting Him means accepting Him as our way of salvation. It also involves living our lives for His glory and pleasure. Finally, a picture of the greatness of Christ should be a picture that we want to show to other people. Just as grandparents find any excuse to show off pictures of their grandchildren, we ought to make opportunities to present Christ to the people with whom we interact.
Christ is great for many reasons. Let's make sure we remember His greatness and act according to it.
He is the image of the invisible God, the firstborn of all creation. For by Him all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities- all things have been created through Him and for Him. He is before all things, and in Him all things hold together. He is also the head of the body, the church; and He is the beginning, the firstborn from the dead, so that He Himself will come to have first place in everything. For it was the Father's good pleasure for all the fullness to dwell in Him, and through Him to reconcile all things to Himself, having made peace through the blood of His cross; through Him, I say, whether things on earth or things in heaven.