As I've said many times, when it comes to Romans 4 Protestants basically truncate the chapter to verses 4:2-8 and ignore the rest of the chapter. This is a shame, for it not only causes an improper emphasis on 4:2-8, but it even results in a mangled reading of 4:2-8. A defining characteristic of all heresies is that they appeal to Scripture in selective sound bites, since appealing to the broader context would expose the error. In this post I'll examine some of that ignored context and show why it does harm to the Protestant appeal to Romans 4.
The passage I had in mind was Romans 4:13-16, coming right on the heels of Romans 4:9-12 (another context routinely ignored by Protestants). In 4:9-12, Paul emphasizes that Abraham's faith was regarded as a righteous act prior to his being circumcised, and that is to prove that justification does not depend on whether one is a Jew or Gentile. That passage shows clearly that Paul was not worried about people trying to save themselves by their own works instead of trusting in Jesus alone by faith alone, but rather that the real problem was Jews thinking themselves superior to the Gentiles and missing the fact justification is apart from the Mosaic Law (Rom 3:28). This sets up Paul for summarizing the heart of his Gospel message:
If Paul was talking about some generic "law" and generic "works" in Romans 4, then this passage really makes no sense. But if Paul is talking about the works of the Mosaic Law, then the beauty of this passage really pops out. What Paul is saying is that God granted a saving "promise" to Abraham back in Genesis, and reception of this "promise" was not conditioned upon adhering to the Mosaic Law which was instituted in Exodus. In fact, Paul says if this "promise" came through following the Mosaic Law, then the prior condition of Abrahamic faith would be nullified.13 For the promise to Abraham and his offspring that he would be heir of the world did not come through the law but through the righteousness of faith. 14 For if it is the adherents of the law who are to be the heirs, faith is null and the promise is void. 15 For the law brings wrath, but where there is no law there is no transgression. 16 That is why it depends on faith, in order that the promise may rest on grace and be guaranteed to all his offspring - not only to the adherent of the law but also to the one who shares the faith of Abraham, who is the father of us all
Using the Catholic principle of Scripture-interprets-Scripture which Protestants don't like, I'll now turn to Galatians 3 which brings about this same message in a more plain manner:
Paul brings out some very amazing points here. First, Paul points out an important nuance which is that the promise God made to Abraham in Genesis mentioned "offspring" (more accurately "seed") in the singular, not the plural. What most Jews were accustomed to doing is reading texts like Genesis 12:7 as speaking of "offspring" in the plural, as in 'one big family'. Really, this "seed" God promised to Abraham was a future son, Jesus! It is through Jesus directly, and Abraham indirectly, by whom all nations would be blessed (Gen 12:3-4 + Galatians 3:8). So Paul is saying it's absurd and wrong to think that the Mosaic Law, "which came 430 years" after Abraham, would somehow steal that privilege and promise from God's covenant with Abraham.15 To give a human example, brothers: even with a man-made covenant, no one annuls it or adds to it once it has been ratified. 16 Now the promises were made to Abraham and to his offspring. It does not say, “And to offsprings,” referring to many, but referring to one, “And to your offspring,” who is Christ. 17 This is what I mean: the law, which came 430 years afterward, does not annul a covenant previously ratified by God, so as to make the promise void. 18 For if the inheritance comes by the law, it no longer comes by promise; but God gave it to Abraham by a promise. 19 Why then the law? It was added because of transgressions, until the offspring should come to whom the promise had been made, and it was put in place through angels by an intermediary.
Thus, the grand realization that Protestants miss is that Paul is not talking about people who are trying to 'work their way into heaven', but rather people who are looking to the wrong covenant to be saved. The Jews thought salvation came through being a member of the Mosaic Covenant, when Paul is saying the Mosaic Covenant never offered salvation in the first place! So even if a Jew kept the Mosaic Covenant, that wouldn't save them (Gal 2:21). Salvation always came through one source, faith in the "seed" of Abraham, Jesus. Protestants made a horrific error by thinking that salvation does come by the Mosaic Law but since we could not keep the Mosaic Law perfectly then Jesus had to keep it perfectly for us!
Paul explains that the Mosaic Law had a temporary function, not an eternal one as Jews and Protestants mistakenly think. The Mosaic Covenant lasted for only about 500 or so years and ended at the Cross. The Mosaic Law was "added" (Gal 3:19) to the picture as God's way of getting mankind ready for the Messiah. The Mosaic Law would formally expose sin ("the law brings wrath") and the need to deal with sin, which simultaneously prefigured and prophesied for us the Sacrifice on Calvary. This is why Romans 5:12-14 says sin and death were in the world before the law was given to Moses and why sin is not formally charged without a law in place.
After realizing this, it is clear that if someone ignores or misunderstands Romans 4:13-16 when reading Romans 4 (and Gal 3:15-19 when reading Galatians 3), then they've missed Paul's entire point! They've come up with "another Gospel" (Gal 1:8), which is unfortunately what Protestantism has done the last 500 years.