Romans 3:19,20

Now what things soever the law saith That is, the Old Testament, for these quotations are not made from any part of the five books of Moses, but from the Psalms and Prophets; it saith to them that are under the law That is, to those who own its authority, to the Jews, and not to the Gentiles. The apostle quoted no scripture against them, knowing it would have answered no end to do so, as they did not acknowledge the authority of the Scriptures; but he pleaded with them only from the light of nature; that every mouth Full of cursing and bitterness: Romans 3:14, and yet of boasting, Romans 3:27, may be stopped And have nothing to plead; and the whole world Not only the Gentiles, but the Jews also; may become guilty May be fully convicted as guilty, and evidently liable to most just condemnation. These things were written of old, and were quoted by Paul, not to make men guilty, but to prove them so. Therefore by the deeds of the law By works of complete obedience to the law of God, whether natural or revealed; there shall no flesh be justified Or pronounced righteous. That the word law must here be taken in this extent, appears evidently from the conclusion which the apostle here draws, and from the whole tenor of his subsequent argument; which would have had very little weight, if there had been room for any to object: Though we cannot be justified by our obedience to the law of Moses, we may be justified by our obedience to God's natural law. And nothing can be more evident, than that the premises from which this conclusion is drawn refer to the Gentiles as well as the Jews; and consequently that law has here, and in many subsequent passages, that general sense. “Every one failing,” says Locke, “of an exact conformity of his actions to the immutable rectitude of that eternal rule of right, mentioned Romans 1:32, will be found unrighteous, and so incur the penalty of the law. That this is the meaning of the expression here used, εργα νομου, works of law, is evident, because the apostle's declaration is concerning πασα σαρξ, all flesh. But we know the heathen world were not under the law of Moses.” For by the law By that written on man's heart, as well as by that revealed, is the knowledge of sin Of our sinfulness and guilt, of our weakness and wretchedness. This strongly implies the broken and disordered state of human nature; in consequence of which, the precepts which God gives us, even the moral precepts, serve only, or at least chiefly, to convict us of guilt, and not to produce an obedience by which we can finally be acquitted and accepted. Whereas, were we not fallen and depraved creatures, by his holy law we should have the knowledge of our being righteous; for when weighed in the balance of it, we should not be found wanting.