The question is not about "ability."
The question is about "nature."
We still have an old nature, the propensity to do evil, which Paul describes in the latter half of Romans 7. There are two natures struggling within him, which at the end of the chapter he cries out and says:
"Who shall deliver me from the body of this death." And the answer immediately comes:
Romans 7:25 I thank God through Jesus Christ our Lord. So then with the mind I myself serve the law of God; but with the flesh the law of sin.
The choice was Paul's, whether to give into sin or not. Sometimes he did. Do you think he lost his salvation when he did? Was Paul perfect?
the question is really about a believer's changed relationship to sin.
You do not have a good handle on this although you are trying to be slick using the terminology of the Lordship guys .
I caught your slick move DHK......but it does not help you here...lol
of course all Christians struggle and are commanded to mortify sin .....that is not the issue at all.