He offered himself to the Jews first because they had the most need of repentance, and only through repentance could they be God's chosen again. Hosea 1:9. God can change who his chosen people are. The act of rejecting Jesus did exactly that (in fact happened before then). They have a promise in the scriptures to be restored as God's chosen people if they repent. Jews avoid all the parts of the scriptures that show that promise because it would force them to admit that they are not his chosen people now. They can be found in Isaiah and Hosea and not just the New Testament.