Therefore, the promise comes by faith, so that it may be by grace and may be guaranteed to all Abraham’s offspring—not only to those who are of the law but also to those who have the faith of Abraham. He is the father of us all.Romans 4:16 NIV
Throughout this fourth chapter of Romans, Paul argued that righteousness comes through faith, not obedience to the law. And Abraham was the star witness in this argument. Paul started his argument by quoting Genesis 15:6, “Abraham believed God, and it was credited to him as righteousness.” God’s crediting of righteousness to Abraham occurred before he was circumcised and before the law. Paul goes on to argue that, because of this, Abraham is the father of all those who have faith. Being Jewish and circumcised does not matter. Nor does being a Gentile and uncircumcised. What matters is having faith like Abraham.
Therefore, Paul says, the promise comes by faith through God’s grace to Abraham and his descendants. The promise of countless descendants, victory over their enemies, and becoming a blessing to all nations (Gen. 15:5, 17:4-8, 22:17-18). This promise was not just to Abraham’s physical descendants. But to all, Jew or Gentile, who have the faith of Abraham. Abraham is the father of all who have faith.
It does not matter what your ancestry is. Your gender, skin color, or political persuasion do not matter. Nothing you can do will earn God’s favor. What matters is your faith—committing your life to what God has said and done. All those who do are descendants of Abraham. And heirs of the promise.