3:6 Even so Abraham BELIEVED GOD, AND IT WAS RECKONED TO HIM AS RIGHTEOUSNESS. 3:7 Therefore, be sure that it is those who are of faith who are sons of Abraham. 3:8 The Scripture, foreseeing that God would justify the Gentiles by faith, preached the gospel beforehand to Abraham, saying, “ALL THE NATIONS WILL BE BLESSED IN YOU.” 3:9 So then those who are of faith are blessed with Abraham, the believer.
Paul stated above that man is not justified by the works of the Law, but through faith in Christ Jesus (2:16). He now provides two arguments for his statement man is justified through faith:
“Abraham believed God, and it was credited to him as righteousness” (3:6; Gen. 15:6). If this was true for Abraham, it should also be true for all Christians (3:7), because they are Abraham’s children (3:29, 7).
God promised to Abraham that “all the nations will be blessed in you” (3:8), which means that “God would justify the Gentiles by faith” (3:8).
“Righteousness” (3:6, 11) means to be put right with God. It has the same meaning as “justified by … before God” (3:11). See also the discussion under 2:21.
Sons of Abraham (3:7) – To be “sons of Abraham” (3:7) or “Abraham’s descendant” (3:29) means to share in the “inheritance” (3:18) promised to Abraham. This is another way of saying that a person is justified (3:7-8; Romans 4:13, 16).
The Jews proudly claimed, “We have Abraham for our father” (Luke 3:8). They thought of themselves as the people elected by God from the nations of the world to receive His special blessings, while the rest of the world is under God’s judgment. But Christ responded, saying, “from these stones God is able to raise up children to Abraham” (Luke 3:8).
Similarly Paul emphasises the promise to Abraham that “All the nations will be blessed in you” (3:8). God called Abraham not only to benefit Abraham and his children, but to benefit the entire world. The major benefit was Christ Jesus, born from the line of Abraham, “in order that in Christ Jesus the blessing of Abraham might come to the Gentiles” (3:14).
Paul adds that believing Gentiles may also count Abraham as their father (3:7). But the statement that “those who are of faith who are sons of Abraham” (3:7) also means that non-believing Jews may no longer count Abraham as their father. As stated by Romans 9:7, “nor are they all children because they are Abraham’s descendants”.