Interpretting Scripture with Paul

Galatians 3:1-6

Paul contrasts the faith and the Spirit with observing the law. He uses rhetorical questions as a device to get his point across. He equates observing the law with human effort. His point is that it is foolish to accept new life by faith but then try to achieve that new life by works (observing the law). The message that Paul received from Jesus and passed on to the Galatians is that we are made righteous by faith in the finished work of Jesus (his death and resurrection). Period.
I wonder if Paul is using the word "foolish" in the OT sense of being morally bankrupt? If so, he is saying that it is morally bankrupt to try to achieve acceptance from God through the things that we do. That is so much stronger than just saying that we are stupid for trying. It flies in the face of what God intended for our lives so by trying to achieve his acceptance through works we are in rebellion against God and insult him: what you did on the cross is not enough - i have to add my own part to it.
I also find it interesting that Paul appeals to Abraham to prove his point. James also appeals to this exact same phrase from Abraham's story to prove his point that faith without works is useless. It is intriguing to me that the Spirit could inspire two different people to use the same phrase to prove what seems like opposing points of view. This means that there must be a bigger picture; maybe it's not "either Paul or James" but "both Paul's and James'" point of view.
If I lived in Paul's day, I would probably have been a Judaizer (if not just a straight up Pharisee). I love structure and rules and I love to build structure around my faith. The problem is that I also love to impose structure on other people as well. God, please forgive me for placing unnecessary burdens on the people around me. Please help me to distill the message of Jesus to its purest form: you are accepted by God in Christ - out gratitude and love for him, I obey. Please help me not to get that backwards: I obey to gain acceptance by God, out of gratitude for my works, you accept me. It sounds absurd when I say it out loud but you know that this is how I live so often. Please forgive me.