Do you think that by these verses we can conclude that Paul was against what he said in Rom_3:31 Do we then make void the law through faith? God forbid: yea, we establish the law.
There was great controversy about what Paul told us about law in the first century, and there still is. I seems to me Paul was reporting on God's voice, and God gave law. I don't see how God, who gave us the law and said it was for our benefit would have Paul say it now wasn't because of His Son.
There is only controversy for those who refuse to believe Paul on the Law. The law is for our benefit in revealing our sin. But it fails in this area...
Romans 7:7-13 What shall we say then? Is the law sin? Absolutely not! Certainly, I would not have known sin except through the law. For indeed I would not have known what it means to desire something belonging to someone else if the law had not said, “Do not covet.”
But sin, seizing the opportunity through the commandment, produced in me all kinds of wrong desires. For apart from the law, sin is dead.
And I was once alive apart from the law, but with the coming of the commandment sin became alive
and I died. So I found that the very commandment that was intended to bring life brought death!
For sin, seizing the opportunity through the commandment, deceived me and through it I died.
So then, the law is holy, and the commandment is holy, righteous, and good.
Did that which is good, then, become death to me? Absolutely not! But sin, so that it would be shown to be sin, produced death in me through what is good, so that through the commandment sin would become utterly sinful.
Disprove what Paul just said and then maybe your case for the Law will have a leg to stand on.