More on Romans 4:
It is important to note that in Romans 4 Paul is teaching that Abraham was Justified by means of the New Covenant of grace, which, because of Christ's anticipated sacrifice, could stretch all the way back to the time of Abraham and beyond, in order to save men. That is why, for example, Hebrews 11:4-7 mentions the prominent saints of old, beginning with Abel and Enoch and Noah, who were saved by faith -- the faith required by the New Covenant in Christ. It is the same reason that Hebrews 11:26 says that Moses "considered the reproach of Christ greater riches than the treasures of Egypt," or why 1 Corinthians 10:4 says that of those who left Egypt "a spiritual rock followed them; and that rock was Christ." The only way anyone was justified in the Old Covenant was on the basis of what Christ would do in the New Covenant.
On the other hand, the circumcision Paul mentions in Romans 4:9-12, and the circumcision in which Abraham and his progeny received, represent the Old Covenant, a covenant of law which had no power to save anyone.
We see the same truth in Romans 9:31-32:
31 but Israel, pursuing a law of righteousness, did not arrive at that law. 32 Why? Because they did not pursue it by faith, but as though it were by works. They stumbled over the stumbling stone..."
Again, the antithesis Paul sets up is one of "faith versus works," or as we have seen before, "grace versus works." The antithesis is not "Jew versus Gentile." The Jew versus Gentile antithesis is only a subset of the main issue, grace versus works.
We know this to be the case also from the context. In Romans 10:5-8 Paul cites Deut 30:12. In the context, Deut 30:8 says, "And you shall again obey the Lord, and observe ALL HIS COMMANDMENTS, which I command you this day." Verse 10 says, "if you obey the LORD your God to keep His commandments and His statutes which are written in this book of the law." There is no singling out of the ceremonial law in this context, yet this is the passage Paul cites to explain the "Law" he had in view in Romans 9:32. Moreover, Deuteronomy 28-29 is the same reference to the Law that Paul cites in Galatians 3:10-12, a passage which refers to the whole Law of Moses. We will see more on this below.
That "grace versus works" is the main issue can be proven beyond much doubt as we see Paul explain the matter in Romans 11:1-6:
1 I say then, God has not rejected His people, has He? May it never be! For I too am an Israelite, a descendant of Abraham, of the tribe of Benjamin. 2 God has not rejected His people whom He foreknew. Or do you not know what the Scripture says in the passage about Elijah, how he pleads with God against Israel? 3 "Lord, they have killed your prophets, they have torn down your altars, and I along am left, and they are seeking my life." 4 But what is the divine response to him? "I have kept for Myself seven thousand men who have not bowed the knee to Ball." 5 In the same way then, there has also come to be at the present time a remnant according to God's gracious choice. 6 But if it is by grace, it is no longer on the basis of works, otherwise grace is no longer grace.
Notice several things in these verses:
1) Paul continues the theme of "grace versus works" that he began in the early part of Romans. 2) We see by the context to which Paul appeals in Romans 11:1-5, which concerns the sin of the Jews in the eighth century BC during the time of Elijah, that the problem of Israel seeking God through their own works rather than through grace is not something that first became a problem in the first century AD when the Jews were mingling Gentiles. Moreover, as Paul looks back on Israel's notorious history, his concern is not "Jew versus Gentile" or "circumcision versus no circumcision." Rather, we see that the problem of Jews seeking God by their works was already occurring in the 8th century BC when almost all of Israel was bowing the knee to Baal. At that time there was only a "remnant" of believers chosen by grace, while the rest perished in their false works. And there were certainly no Gentiles to whom the Jews could boast of the graces they received from God.
We can also prove the point by what Paul says in Galatians 5:4:
"And I testify again to every man who receives circumcision, that he is under obligation to keep the whole Law. 4 You have been severed from Christ, you who are seeking to be justified by law; you have fallen from grace."
"Works of the Law" - Page 10