The Defence of the Law
Keeping the rules is not the gospel message. A person is made right with God by grace. Paul then anticipates a misunderstanding: is the law sin? No, but it does show him what is right and wrong so he can see there is sin in his life. The law gets to the heart: the problem is the sin within us. Paul was brought up under the law but then it came alive and he could no longer ignore it. He "died"; he could never be that proud Pharisee again. What killed him wasn't the law but sin. This is why we need Christ.