“God is a Jew.”
You can’t get around it. The conclusion is inevitable. If Jesus was a Jew, and if Jesus was God, then God was a Jew–and assuming He doesn’t change, He remains as such to this day. Of course the Bible anticipates this reality in the Old Testament when He declares Himself as “the God of Israel” (or a similar iteration) over 300 times. But the real issue isn’t so much about ethnicity as it is the kind of story–the “Jewish metanarrative”–that is associated with God’s covenantal dealings.
By the time of the New Testament, the Jewish story had greatly matured and was represented by such phrases as “the kingdom of God,” “the resurrection of the dead,” “the last day,” “the son of David,” etc. Jewish and secular historical scholars for the last hundred years have recognized that these phrases from the NT fit quite comfortably within the preexisting Jewish metanarrative of the day. But because of the implications of the incarnation, Evangelical scholars (and the multitudes who follow them) have generally refused to acknowledge the Jewish realities that infuse the New Testament.
Unfortunately for them (especially as the end of the age closes upon us), God does not change, and therefore “the gifts and the calling of God are irrevocable” (Rom 11:29). Though God is indeed “the Lord of all the earth” (Ps. 97:5; Zech. 6:5), including all of the Gentiles (cf. Rom. 3:29), He will always be first and foremost the God of Israel. And the words of the angel Gabriel will indeed come to pass: “He will be great and will be called the Son of the Most High. The Lord God will give him the throne of his father David, and he will reign over the house of Jacob forever; his kingdom will never end.” (Luke 1:32-33).
Gabriel could have declared any of the Gentile metanarratives rampant in the church today, but he clearly confirmed the popular Jewish metanarrative of the day. The incarnation clearly means that the vision of the Law and the Prophets will come to pass as literally spoken. And the cross and the resurrection prove it to be so (cf. Acts 1:7; 3:21; 5:31; etc.).