The law was never intended to give steps 1 through 600 for pleasing God. Anyone of an orthodox Jewish mindset believed it was. The Pharisees prided themselves on their ability to keep the law. The fact was, that was not the intent of the law.
Look at Galatians chap. 3 and Romans chap. 3.
So, Paul comes to this part of His letter and makes a point to those who know the law (See vs. 1)
The woman is bound by law to her husband, but if He dies, she is loosed from his law, and free to marry another. Through Jesus Christ, there has been a death. We, through Christ, are dead to the law. The law was a picture of the holy standard of God. It revealed sin in us. Anyone who tried to keep the law found they could not, and the law reminded us through its endless sacrifices that we were not free from our sins. Rememberance was made of those sins every year.
Now, since the law brought to me knowledge of sin, and made my sin exceeding sinful by showing me how far short of God's holy standard I was coming, does that mean that the law was sin? Absolutely not. It was a picture of God's holy standard.
Verse 13 really ties it down. (13) Was then that which is good made death unto me? God forbid. But sin, that it might appear sin, working death in me by that which is good; that sin by the commandment might become exceeding sinful.
The law exposed my sinful state.
Paul then goes on to describe the utter impossibility and sheer frustration experienced by trying to be good by keeping the law, when the law only made sin come alive to him. This is the futility of trying to please God by keeping the law. When he knew to do good, he found himself always falling short of it.
He concludes by saying, who is going to get me off this impossible treadmill? Who is going to deliver me from this rat race of self effort in trying to keep the law and finding myself always sold under sin? I thank God through Jesus Christ our Lord.
Jesus (see Rom 7:4) is the one who delivers us from the body of this death.
I would also suggest reading Hebrews chapter 10 on this same issue. (The strong doctrinal parallels between Romans and Hebrews are one reason I personally believe the author of Hebrews to be Paul.) Under the law, man was prevented from going "behind the veil" in to the presence of God due to his sinful state. But because Christ is now that veil, that doorway to the very presence of God, we can now go through Him into the very holy of holies, perpetually, not just once per year after intricate and exhaustive cleansing ceremony.
Anyway, hope that helps
Travis