Romans 3:
30 since there is one God who will justify the circumcised by faith and the uncircumcised through faith. 31 Do we then make void the law through faith? Certainly not! On the contrary, we establish the law.
Some background & then a parsing of Rom 3:31
1 John 3:4 Whoever commit's sin transgresses also the law: for sin is the transgression of the law.
(NOTE: Sin is the transgression of God's heavenly/supreme laws)
We've all broken God's law & deserve it's sentence/wage/payment invoked in (Rom 6:23 DEATH).
No one can say he is not a sinner until some means is provided (not to take away the law) but to remove the sin, which is the transgression of the law.
Context from vs 21 to 31 if: Righteousness/Justification by FAITH void of Mosaic law.
Rom 3:
21 But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;
(NOTE: The righteousness of God """Jesus Christ""" has been made known)
22 Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:
(NOTE: Jesus is the righteousness of God. Jesus willingly exchanged His sinless righteousness for our sinfulness. When we place our FAITH in His FAITHFUL sin atoning work & resurrection. Our Great High Priest (Heb 4:14) takes away our sins, by imputing them (Rom 4:8 11, 22, 23, 24, Ja 2:23) onto himself & imputing His righteousness onto the believer. Jesus takes away our sin & we become the righteousness of God in/thru Christ (2 Cor 5:21)
23 For all have sinned, and come short of the glory of God;
24 Being justified freely by his grace through the redemption that is in Christ Jesus:
(NOTE: Justified freely = Judicially declared righteousness by a sovereign God. When we place our FAITH in Jesus sin payment & resurrection)
25 Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;
(NOTE: Jesus shed blood is the propitiation =atoning sacrifice, that declares his righteousness (via his resurrection) enabling Him to remiss = pardon sins. When we place our FAITH in Jesus sin atoning payment & resurrection. He forgives ALL our sins)
26 To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.
(NOTE: This verse declares Jesus righteousness & declares Jesus the justifer of those who believe/have faith in Christ. Not those that follow/keep the law)
27 Where is boasting then? It is excluded. By what law? of works? Nay: but by the law of faith.
(NOTE: "THE LAW OF FAITH")
28 Therefore we conclude that a man is justified by faith without the deeds of the law.
(NOTE: Man is justified = Declared righteous = by "FAITH" without the deeds of the law).
29 Is he the God of the Jews only? is he not also of the Gentiles? Yes, of the Gentiles also:
(NOTE: He is God of BOTH, Jew & Gentile)
30 Seeing it is one God, which shall justify the circumcision by faith, and uncircumcision through faith.
(NOTE: God justifies = Declared righteous. BOTH the circumcision = JEW, by "FAITH". And uncircumcision = GENTILES through "FAITH")
31 Do we then make void the law through faith? God forbid: yea, we establish the law.
(NOTE: If you'll read verse 31 in context. Its the new covenant LAW OF FAITH that Christ has established, just "REREAD vs 27".)