Paul's words in Col. 3:1-4 cut across time: they begin with the past, come into the present, and look to the future. In all these phases we are united to Christ. Union with Christ has been called the "umbrella doctrine" because it covers the entire Christian experience. "In Christ" is the fundamental expression used over and over in Paul's letters to describe the position of the Christian in this world. In Gal. 2:20 we learn that we have been united with Christ in his death. All of our subjective blessings are based on his objective work on the cross. As Michael Horton says, "If Christ remains outside of us , it's useless to us - we must cash in through personal faith in Christ." When Christ arose and ascended, we also rose and ascended with him, not bodily, but spiritually. So in our present experience on earth, we walk by faith via the enablement of the grace of Spirit, to live our daily lives so as to please him. In 1 Thessalonians 4:13-18 we read about our future at Christ's return: the raising of our lowly bodies from the grave to be changed like unto Christ's glorious resurrection body. Thus our present spiritual union will also become physical by the power of God.