the law is spiritual

-from Martin Luther's Intro to Romans

"In chapter 7, St. Paul says, "The law is spiritual." What does that mean? If the law were physical, then it could be satisfied by works, but since it is spiritual, no one can satisfy it unless everything he does springs from the depths of the heart.

But no one can give such a heart except the Spirit of God, who makes the person be like the law, so that he actually conceives a heartfelt longing for the law and henceforward does everything, not through fear or coercion, but from a free heart.

Such a law is spiritual since it can only be loved and fulfilled by such a heart and such a spirit. If the Spirit is not in the heart, then there remain sin, aversion and enmity against the law, which in itself is good, just and holy."