Which law is Paul speaking of in Romans 3:31?

Which law is Paul speaking of in Romans 3:31?

The verse reads,

Rom 3:30-31  Seeing it is one God, which shall justify the circumcision by faith, and uncircumcision through faith.  31  Do we then make void the law through faith? God forbid: yea, we establish the law.

The short answer for what is the law in this verse:

One could point to the original law, the Mosaic Law, aka, the moral law, which will suffice in the context of this verse, but it can also be extended to define any set of external rules or regulations that are enforced upon us in expectation of obedience, conduct, and performance. Law is typically what we DO in our own strength to appease the will of a governing power.

However, asking this question does not fully explain what Paul is stating in this passage. Simply knowing the definition of the law does not inform us what Paul really mean in the above passage.

The proper context of the verse can be understood as follows:

Paul is dealing with the concept of salvation. He is informing the reader that faith is the only accepted means to be saved. The law cannot save anyone. So, if faith saves, do we make void the law? Does salvation by faith mean that God’s law is annulled, or abolished? Does this open the door for license to sin?

For all these questions, Paul says, “God forbid”. The literal idea here is “let it not come into being.” God’s standards of righteousness do NOT change. There is a purpose to the law. It reveals that God’s person and works are absolute. The only way we can fellowship with God, therefore, is by faith, because it is impossible to measure up to God by works. If our righteousness is as filthy rags to God, we have no hope to appease God by works, so by His grace, we can receive His righteousness, as a gift, through faith in Jesus Christ.

So how is the law established by faith?

This arrangement can only work if something is in place that has already met the standard or requirements of God’s law. In scripture we know this to be Jesus Christ. Therefore, the principle of faith gives meaning to the true idea of the law. Justification by/through faith is consistent with the law because it affirms God’s need to penalize sin and resolves that need by Jesus’ paying that penalty.

God meets the purpose of the law by saving people who believe in Jesus Christ. The law is fulfilled in this arrangement as God hath set forth Jesus Christ to be a propitiation through faith in his blood, and thus declares believers in Christ to be righteousness by imputation of Christs righteousness. This is why the verse says, “the uncircumcision are justified THROUGH faith”. Thus, we are justified not BY our own righteousness (or obedience to the law), which is Israel’s requirement, being under the administration of the law, but THROUGH the already established and accepted righteousness of Jesus Christ, which we are gifted by God, because we are under the administration of grace.