Romans 7:15

Only the hypothesis of slavery explains his acts. For what I do οὐ γινώσκω, i.e., I do not recognise it as my own, as a thing for which I am responsible and which I can approve: my act is that of a slave who is but the instrument of another's will. οὐ γὰρ ὃ θέλω κ. τ. λ. There is “an incomprehensible contradiction in his action”. κατεργὰζεσθαι is to effect, to bring about by one's own work; πράσσειν is to work at, to busy oneself with, a thing, with or without success, but with purpose; ποιεῖν is simply to make or produce.