What shall we say then? Is the law sin? God forbid. No, I had not known sin, but by the law: for I had not known lust…
In this picture of his inner life Paul gives us, without intending it, a very high idea of the purity of his life as a child and a young man. He might, when confronted with the nine commandments, have to the letter claimed for himself the verdict, Not guilty, like the young man who said to Jesus, "All these things have I kept from my youth up." But the tenth commandment cut short all this self-righteousness, and under this ray of the Divine holiness he was compelled to pass sentence of condemnation. Thus there was wrought in him, Pharisee though he was, without his suspecting it, a profound separation from ordinary Pharisaism, and a moral preparation which was to lead him to Christ and His righteousness. To this so mournful discovery was added (δε ver. 8) by and by a second and more painful experience.
Parallel VersesKJV: What shall we say then? Is the law sin? God forbid. Nay, I had not known sin, but by the law: for I had not known lust, except the law had said, Thou shalt not covet.
WEB: What shall we say then? Is the law sin? May it never be! However, I wouldn't have known sin, except through the law. For I wouldn't have known coveting, unless the law had said, "You shall not covet."