I wasn't sure if I should answer the law part here or in the "delivered from the law" thread so I posted separately, just in case you wanted to move it to keep everything in one thread.
The fact that Paul suffered is clear, but the question is, did he suffer under grace, or did he place himself back under the law to suffer under sin. Again, that we struggle with sin, is one thing, that we struggle with sin under the law, is another. And, did Paul really not know who would deliver us from the body of sin? Of course he did. Then why ask? Because he is describing his experience when he was not delivered from the law and not under grace, when he did not know who Jesus was at all. That is why Romans 8 describes NOW, as opposed to Romans 7's THEN.
Though people understand that we have a struggle with sin. I think they mistake Romans 7 as a description of that. Romans 7 only describes struggle with sin, when we are under the law, which we are not supposed to place ourselves under for righteousness. Our struggle with sin is under grace, wherein we are delivered from, NOT under the law, wherein we are kept in sin.