Romans 8:11 says the Spirit quickens or GIVES LIFE (resurrection life) to our mortal flesh so we are no longer debtors to live after the flesh, which is what Paul described in
Romans 7. That's the newness of life in
Rom 6:4.
The sin in Paul's flesh compelled him. And when we read we are no longer debtors to the flesh in
Rom 8:12 ,it is because of the Spirit quickening us. Notice Paul did not say we are no longer debtors because WE CHOOSE to serve God, as if CHOICE was the issue all along. It says the Spirit quickening our mortal flesh is the reason we don;t have to live after the flesh.
And Ro 6:13 also says we yield OUR MEMBERS to God as instruments of his righteousness. Instruments means that HE ACTUALLY USES THEM! It's not saying we choose to DO what is right, and that is making them his instruments. When something is someone's instrument they actually and directly use that something! That is what the quickening of our mortal bodies is talking about in 8:11. We're not puppets, though. But we cooperate with the Spirit and act when empower so we can live over a life of sinful activity.
I think Barnes got it right:
He had shown that Christians were freed from the Law as a matter of obligation, and yet that this freedom did not lead to a licentious life; Rom. 6. And he now proceeds still further to illustrate the tendency of the Law on a man both in a state of nature and of grace; to show that its uniform effect in the present condition of man, whether impenitent and under conviction, or in a state of grace under the gospel, so far from promoting peace, as the Jew maintained, was to excite the mind to conflict, and anxiety, and distress.
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It is ..designed to group together the actions of a man’s life, whether in a state of conviction for sin, or in a state of grace, and to show that the effect of the Law is everywhere substantially the same. It equally fails everywhere in producing peace and sanctification.
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Rom 7:21 - The meaning is this, “I find a habit, a propensity, an influence of corrupt passions and desires, which, when I would do right, impedes my progress, and prevents my accomplishing what I would.” Compare Gal_5:17. Every Christian is as much acquainted with this as was the apostle Paul.
He nailed it!
The tendency of LAW on BOTH an unrepentant Jew AND ANYONE in grace is to impede what we want AND CHOOSE to do.