Let's be honest: were the Lord to have restricted salvation to the Jews only, we would be lost!
Since Israel is God's light to the nations, it was His predetermined plan that this light should shine to the Gentiles. Remember Abraham was given three promises from God in Genesis 12-17:
Paul asks in Romans 3:1, "What advantage has the Jew?" His answer was that they had the oracles [Word] of God, and Christ would be born of the natural seed of Abraham, thus fulfilling God's promise to him that he would bless the entire world.
Taken from "The Church That Changed" by Wisdom for the Heart Ministries (used by permission).