For we know that the law is spiritual - in its demands.
but I am carnal - fleshly (see on Rom 7:5), and as such, incapable of yielding spiritual obedience.
sold under sin - enslaved to it. The āIā here, though of course not the regenerate, is neither the unregenerate, but the sinful principle of the renewed man, as is expressly stated in Rom 7:18.