It is an all-too-common assumption that the concept of the Trinity is a purely Christian idea. But the idea of a God being a three-in-one unity actually has its roots in foundational Judaism and in the Hebrew Scriptures. Even the concept of the Holy Spirit, the Ruach Ha-kodesh, originates in the Hebrew Scriptures—as early as Genesis 1.
Yet, modern Judaism has reached an overwhelming consensus that one cannot believe in the Trinity and be Jewish. Rabbi Stanley Greenberg argues that “Hebrew Scriptures are clear and unequivocal on the oneness of God.… Monotheism, an uncompromising belief in one God, is the hallmark of the Hebrew Bible, the unwavering affirmation of Judaism and the unshakable faith of the Jew.” He continues, “Under no circumstances can a concept of a plurality of the Godhead or a trinity of the Godhead ever be based upon the Hebrew Bible.” Even if what Christians believe is monotheistic, it does not seem to be monotheistic enough to qualify as true Jewishness.
Many Jewish people do believe in the Trinity.
But if we are to examine this line of thinking, it is best to begin with the very source of Jewish theology and the only means of testing it—the Hebrew Scriptures. We should be open to exploring and understanding the nuances of the Jewish roots of the Trinity because many Jewish people do believe in the Trinity! If we go back to the Scriptures, the case is clear, and this article will walk you through that case. Our understanding hinges on the Hebrew language, so to the Hebrew first we shall turn.
A Jewish View of the Trinity Based on the Hebrew Scriptures – Jews for Jesus
His eye is on the sparrow 