Who is the 'seed' of Abraham through whom all nations would be blessed?
Scripture identifies the seed of Abraham as his offspring, the nation of Israel, through whom all kindreds of the earth would be blessed. Israel was to receive the Redeemer, the Messiah, the King, and the Kingdom, and through Israel God would gather the Gentiles. Peter preached this on covenant ground.
Les explains that Peter is preaching to a Jewish crowd in Acts 3, reminding them they are the children of the prophets and of the covenant God made with their fathers. God told Abraham, "In thy seed," that is Abraham's seed, "through the nation of Israel, all the kindreds of the earth would be blessed." Les emphasizes that all prophecy is directed to the nation of Israel, because they are at the core of these prophetic events, even the Book of Revelation. Peter stands on covenant ground: Israel was to receive the Redeemer, the Messiah, the King, and the Kingdom, and it would be through Israel that God would gather the Gentiles. God had not cast off the Gentiles, but He would use Israel.
Ye are the children of the prophets, and of the covenant which God made with our fathers, saying unto Abraham, And in thy seed shall all the kindreds of the earth be blessed.