Rom. 4:20-21 ... "With respect to the promise of God, he did not waver in unbelief, but grew strong in faith, giving glory to God, and being fully assured that what He had promised, He was able also to perform."
For many years after Christianity was launched in the world at Jerusalem in 33 A.D. it had a very strong Jewish identity. Within the church the influence of Jewish thought and customs was indeed powerful and posed no little challenge to Gentiles who came into the church without this mental and cultural baggage. One of these challenges specifically centered on the doctrine of justification. Jews thought that because they were genetically descended from Abraham justification was their birthright. Abraham was their spiritual hero, being the "father of the faithful" and having the distinction of being called "the friend of God," (Jas. 2:23). His faith was the epitome of human response to divine promise, so much so that Gen. 15:6 reports that "he believed in the Lord; and He reckoned it to him as righteousness," (quoted by Paul in v.3). Since all of Israel were genetically in Abraham, (cf. Heb. 7:9-10), when righteousness was conferred upon him in reward for his faith, it was conferred upon every unborn Jew as well. To be born, therefore, in descent from Abraham was to be justified from the day of one's birth. The Jews also thought they accumulated righteousness through the scrupulous performance of the rituals and other religious acts taught in the Mosaic Law. The Pharisees carried this doctrine to the ultimate, hedging the Law about with endless deductions from Mosaic statutes to ensure that everything would be done that could be to increase one's righteousness by participation.
In Romans 4 Paul refutes the entire Jewish doctrine of justification. He points out that Abraham was not saved by works, but rather through his faith which prevented him from "wavering" as he considered "the promise of God." Even the works that he did, in response to God's commandments, were not the works of the Mosaic Law, for that law was still some four hundred years in the future after Abraham. In the previous chapter (vs. 28-29) Paul had argued that being a Jew genetically was unimportant. What mattered was being a Jew spiritually, an identity available to anyone through faith in Christ and obedience to His gospel. The same logic applies to being a "child" of Abraham. There is no distinction in being lineally descended from Abraham; his righteousness is not inherited by his offspring. It is only when, like that patriarch, we put our faith in God who "raised Jesus our Lord from the dead," that our own faith is reckoned to us for righteousness, (see vs. 23-24). Although this faith involves obedience (Rom. 1:5), it is not meritorious obedience that obligates God to save.
The lesson we must learn from this is that we cannot construct a doctrine of justification to suit ourselves. We must study the Scriptures to see what is taught there about the problem of human sin and how it may be forgiven. As our text says, what God has promised, He is also able to perform. But the crucial point is "what God has promised." It is not for me or anyone else to speak for God and demand that others accept my word about justification. God has already spoken clearly and has given us the intelligence to understand what He has said. He will be pleased if, like Abraham, we respond in simple faith to the gospel. When we have done that, just as He has promised, He will reckon our faith unto us for righteousness, and we will be justified in the Lord Jesus Christ.
