Verse 20 spells out for us what this experience of death to law and life to God is like. “I have been crucified with Christ; it is no longer I who live, but Christ who lives in me; and the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.”
What does it mean to be crucified with Christ? I think it means this: First, that the gruesome death of the all-glorious, innocent, loving Son of God for my sin is the most radical indictment of my hopeless condition imaginable. The crucifixion of Jesus is the open display of my hellish nature. And, second, when I see this and believe that he really died for me, then my old proud self which loves to display its power by climbing ladders of morality and intellect and beauty and daring dies. Self-reliance and self-confidence cannot live at the foot of the cross. Therefore, when Christ died, I died.
What then remains? Verse 20 puts it two ways. First, “Christ lives in me.” Christ remains. He rose from the dead, and he took over where the life of pride and self-direction had died. The great and awesome mystery of the gospel is “Christ in you, the hope of glory” (Colossians 1:27). Brothers and sisters, this is conversion. A Christian is not a person who believes in his head the teachings of the Bible. Satan believes in his head the teachings of the Bible! A Christian is a person who has died with Christ, whose stiff neck has been broken, whose brazen forehead has been shattered, whose stony heart has been crushed, whose pride has been slain, and whose life is now mastered by Jesus Christ. “It is no longer I who live, but Christ who lives in me!”
But verse 20 puts it another way, too: “And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.” There is a new “I”—I do still live. But look who it is. It is no longer an “I” who craves self-reliance or self-confidence or self-direction or self-exaltation. The new “I” looks away from itself and trusts in the Son of God, whose love and power was proved at Calvary. From the moment you wake in the morning till the moment you fall asleep at night, the new “I” of faith despairs of itself and looks to Christ for protection and the motivation, courage, direction, and enablement to walk in joy and peace and righteousness. What a great way to live!