Romans 1:16 For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek.
Salvation has come to both Jew and Gentile. To the Jew first because the message of the Messiah was first given to them. The message of Christ would then be brought to the Gentiles.
Matthew 28:19 Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: 20 Teaching them to observe all things whatsoever I have commanded you: and, lo, I am with you always, even unto the end of the world. Amen.
Paul would write here in Romans 4 that this blessedness had come both to the Jew and to the Greek. He would point out how this promise, the promise of salvation by the righteousness of the coming Messiah, came to Abraham well before Abraham was circumcised. The Jews looked to circumcision as their justification before God. It was a sign of following God’s law. Paul has already shown us how no flesh will be justified by the law in the eyes of God in Romans 3:20. God made this promise to Abraham before he was circumcised. The Jews had confidence in their bloodline. Paul was carefully showing his audience that bloodlines, works, or any other aspect that pointed to the character or doings of man were in no way associated with their justification before God. God made this promise to Abraham who was at the time uncircumcised. He was in fact not even a Jew, he was a Gentile. His bloodline and his performance did not commend himself to God. We have the law of works and the law of faith. That law of faith tells us that God was in Christ reconciling man to Himself. This was done completely outside of the input of Abraham.
Romans 4:9 Cometh this blessedness then upon the circumcision only, or upon the uncircumcision also? for we say that faith was reckoned to Abraham for righteousness. 10 How was it then reckoned? when he was in circumcision, or in uncircumcision? Not in circumcision, but in uncircumcision.
Paul points out again that faith, otherwise known as the law of faith or the faith of Christ, was imputed or reckoned to Abraham as righteousness. The promise that Christ would come was Abraham’s hope. It was not just his hope, but it was the guarantee from God that he would be made righteous by the coming of the Savior. God would provide Abraham what was needed for his salvation. This was a promise, it was a prophecy from God of a coming event.
Genesis 22:11 And the angel of the Lord called unto him out of heaven, and said, Abraham, Abraham: and he said, Here am I. 12 And he said, Lay not thine hand upon the lad, neither do thou any thing unto him: for now I know that thou fearest God, seeing thou hast not withheld thy son, thine only son from me. 13 And Abraham lifted up his eyes, and looked, and behold behind him a ram caught in a thicket by his horns: and Abraham went and took the ram, and offered him up for a burnt offering in the stead of his son.
In Genesis 22 we see how Abraham took his son Isaac to Mount Moriah to offer him a sacrifice at the command of God. Just as Abraham was to complete the commandment of God an angel called out to him. Abraham would look and see a ram caught in the thicket by his horns. This is the substitution that God had promised. This pictured the coming Savior and how He would be the sacrifice. Abraham believed God. Abraham had faith in that faith who would come.