"The law is a mirror to show a person what he is like, a sinner who is guilty of death, and worthy of everlasting punishment. What is this bruising and beating by the hand of the Law to accomplish? This, that we may find the way to grace. The Law is an usher to lead the way to grace. God is the God of the humble, the miserable, the afflicted. It is His nature to exalt the humble, to comfort the sorrowing, to heal the broken-hearted, to justify the sinners, and to save the condemned. The fatuous idea that a person can be holy by himself denies God and the pleasure of saving sinners. God must therefore fist take the sledge-hammer of the Law in His fists and smash the beast of self-righteousness, and its brood of self-confidence, self-wisdom, self-righteousness, and self-help. When the conscience has been thoroughly frightened by the Law it welcomes the Gospel of grace with its message of a Savior who came into the world, not to break the bruised reed, nor quench the smoking flax, but to preach glad tidings to the poor, to heal the broken-hearted, and to grant forgiveness of sins to all the captives.
Once the Law has done its proper work, we must then say to the Law: 'Mister Law, lay off him. He has had enough. You scared him good and proper.' Now it is the Gospel's turn. Now let Christ with His gracious lips talk to him of better things, grace, peace, forgiveness of sins, and eternal life." ~ Martin Luther, Commentary on the Epistle to the Galatians