The law was given by God in order to reveal the evil of sin. The law was never meant to justify but was only given in preparation of the promised redemption that was to come and eventually in the fullness of time was accomplished through Jesus Christ the Son of God. Indeed,the law today is still used for this very purpose; to convince man of his sin and need for a Savior.
Written in the hearts of mankind is the moral law of God.
”Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another;”
For when the Gentiles, which have not the law, do by nature the things contained in the law, these, having not the law, are a law unto themselves: Romans 2:14
BUT according to Romans 7,man is unable to obey the law in its entirety. He knows in his conscience what is good and what is right but because of his sin nature he cannot obey it. Rather than bringing life the law brought death.
“Wherefore the law is holy, and the commandment holy, and just, and good. Was then that which is good made death unto me? God forbid. But sin, that it might appear sin, working death in me by that which is good; that sin by the commandment might become exceeding sinful.For we know that the law is spiritual: but I am carnal, sold under sin.” Romans 7:12-14
“O wretched man that I am! who shall deliver me from the body of this death? I thank God through Jesus Christ our Lord. So then with the mind I myself serve the law of God; but with the flesh the law of sin.” Romans 7:24,25
The law is spiritual but man is carnal, sold under sin. Carnal unsaved men are slaves to sin and obey the dictates of the sinful nature even though the conscience knows right from wrong. If the carnal man ignores the conscience repeatedly he will eventually become so hard that he simply cannot without God’s miraculous intervention, receive Christ.
“For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit. ” 1 Peter 3:18