Romans 3:20

because by the works of the law shall no flesh be justified in his sight; for through the law cometh the knowledge of sin. [Having, by his quotations from the Old Testament, shown that the Jew was sinful, the apostle sets forth the result of this sin. Does the law provide any remedy? Is the Jew right in hoping that it shall afford him immunity from his guilt? These questions have been for some time before the apostle, and they now come up for final answer. We, says he, universally accept the truth that when the law speaks, it speaks to those who are under it. If, therefore, it has no voice save condemnation--and it has no other--and if that voice is addressed particularly to the Jew--and it is--his state is no better than that of the Gentile; he is condemned; and the law thus speaks for this very purpose of silencing the vain, unwarranted confidence of the Jew, that he may see himself in the same condition as the Gentile, and brought, with the rest of the world, under the condemnation of God; and there can be no legal escape from this condemnation, because, by the works of the law, it is impossible for humanity, in its frailty, to justify itself in God's sight--nay, the law works a directly contrary result, for through it comes the knowledge and sense of sin, and not the sense of pardon or justification.]