Do you think some of the OT is still binding?
The OT contains the Gospel of Jesus Christ. He is in the law and teh Prophets.
The OT will never be abolished at any level. Jesus Christ has completed it, fulfilled it.
Now, due to the revelation of the Teaching of Jesus Christ we may read teh law andunderstand just what He has fulfilled, and how it is yet being fulfilled.
We understand by Christ's teaching that the law is not dead or abolished, and it is yet to be obeyed as best possible given each of us by the grace and mercy of His salvation. He is the perfect One for each of us, and to say we do not sin is saying He is lying about the law still being in effect, according to His teaching.
Anyone who claimes to believe Jesus Christ yet finsds study of the law and adherance to it as it is being fulfilled still has blinders on, that is the veil of Moses.
We are free indeed of the curse of the law, and we are free of the guilt of our breaking it, but we are not to live in sin as a way of life. We reject all manner of sin while striving to be like Jesus Christ our Salvation,n but we must believe Him,.
The best litmus test is if a person believes Him about the law or goes to all extremes to say it is abashed, that latter is a lie, and not graced by the truth of the Salvation of Jesus Christ, His Word.