I do not understand my own actions. For I do not do what I want, but I do the very thing I hate. Now if I do what I do not want, I agree that the law is good. So then it is no longer I that do it, but sin which dwells within me. For I know that nothing good dwells within me, that is, in my flesh. I can will what is right, but I cannot do it. For I do not do the good I want, but the evil I do not want is what I do.
I think we've all felt what St. Paul describes in this passage. It's that “what am I doing?” feeling. It is the strange feeling that we are letting something else determine our stupid sinful choices, coupled with the awareness that it is truly us who are letting that happen. We're not acting with freedom exactly, but we can't whine about the “devil making us do it” either. We are what Paul calls “slaves to sin.” We can only acknowledge that we are somehow not really willing to leave off giving the devil his due and start giving God our obedience. One happy consequence of realizing we are spiritual wimps in the war on sin in our hearts is the concurrent realization (if we are paying attention) that we must therefore look somewhere other than in the mirror for our strength. Paul puts this with refreshing candor: “Nothing good dwells within me, that is, in my flesh.” He does not mean there is something evil about the body per se, but rather that, before baptism, our being suffers from the lack of communion with God (“Original sin” is the technical term) and that, after baptism, we go on struggling with the effects of sin that tend to incline us away from God. How do we triumph in this struggle? Not by worshipping our will power. That is simply to look in the mirror more closely. No, Paul tells us plainly, the power to overcome our imperfect humanity can only come from him who lived a perfect human life. “Thanks be to God, through Jesus Christ our Lord” (Romans 7:25).