If the doctrine of the a triune God is true, then why would God have hammered so hard in the Torah that “God is One”, forbid worshipping of anything else, and told the Jews to reject any prophet, no matter how seemingly good or accurate his predictions were, if all along “the plan” was to bring this “Son of God” who was also God, and this “Holy Spirit” who was also God, both of whom are to be worshipped as Yahweh was?  This seems, to me, to be setting up the Jews to reject anything that is claiming to be, or pointed at as “god” of some sort that is not directly the great I AM.