“What then shall we say that Abraham, our forefather according to the flesh, discovered in this matter? If, in fact, Abraham was justified by works, he had something to boast about—but not before God. What does Scripture say? “Abraham believed God, and it was credited to him as righteousness.”
When I worked with children’s church, one of their favorite songs was ”Father Abraham”. Many of you know it as an action song. The theology of the song is the teaching of Romans 4. Its words include “Father Abraham, had many sons and I am one of them and so are you, so let’s just praise the Lord”. The children would move about with arms, feet, head and body.
The Bible teaches I am one of the Sons of Abraham by faith. That message did not sell well to the Jewish audience in Rome. For the Gentiles to be included as sons of Abraham, he would have to convert to Judaism, be circumcised, baptized, and proclaim a certain doctrinal statement denouncing his former faith. He would have to commit to following the laws of the Jews.
Arabs also consider themselves to be the sons of Abraham for he is also the father of Ishmael, the genealogical line of the Arab people.
For true faith, the Jews point to the son of the promise, who was Isaac, and point out the importance of circumcision for the covenant people. Abraham was instructed by God to circumcise his son as a sign that he was part of the covenant people of God.
The Jews held Abraham up as the premier example of a man who had been saved by his works, when he obeyed by going to a foreign land. They believed that he was the epitome of a life lived right. They believed that God accepted and justified Abraham because He had earned it. He obeyed the law of circumcision.
Since Abraham came up as an illustration of justification by his obedience, it proved the point rabbis taught, that salvation was for the Jew and was tied into the Old Testament laws to follow with Moses. Paul took the very Scriptures they used, put their teaching into the complete context, and came to a very different conclusion. He showed how Abraham illustrated the very teaching - that we are justified by our faith.
Among some of the points, Paul makes clear - the law did not come until much later. All the rules followed by the Jews had never been established at Abraham's time. There was something else in the relationship between Abraham and God that made him justified. It was faith.
Justification brings great joy to both Jew and Gentile. After Jesus arrived, they learned Christ’s suffering and death met the demands of the law of God. He bought justification through their faith in Jesus Christ and His work of mercy on the cross.
Key question - What does the Scripture say? vs 3 "Abraham believed God, and it was credited to him as righteousness." This is true of all believers in both the Old and New Testament.
We will see how this truth brings us the great joy pointed out in the rest of chapter 4.
Dale

