Yes, that sin is the law. Now I know others will think the law is not sin.... but yes. It is doing despite to the spirit of Grace and the blood of Jesus Christ , to say we now need to go by that law.
That was made abundantly clear by all of the Apostles. Peter certainly nailed it down by calling it a bondage which was too hard for any of the, past or present. It was the main trouble to that early church. Paul said they were subverting their souls to tell them they need to keep the law. Peter also said this.
So that proves it is the BESETTING SIN.
We certainly see that it was besetting that early church. We today, see it even more. We now see old jewish stuff set way up above Grace, worship in spirit and in truth, without the works of the law.
So , this besetting sin is trying to take or tell Christians that they must go back and keep the law of Moses, either to be saved, or to now have righteousness.
Never knew this before. Thanks for this study.