The basic contribution of Judaism to Western civilization is monotheism. Understood from the standpoint of Jewish tradition, Abraham was the first monotheist. He left polytheism behind to follow the directions of the one God. The Tanakh itself gives evidence that significant numbers of ancient Israelites worshipped multiple deities.(Rabbi Shofet) Jewish leadership called upon Israel to worship the one God with whom they had a covenant relationship. But as Tanakh develops there is an increasing emphasis on the unreality of other "gods" in comparison to the one God.
The God of Israel is the God of Abraham, the God of Isaac, the God of Jacob. That is, he is the God that Abraham, Isaac, and Jacob knew. He is the God who bound himself inextricably with his covenant people and who remains faithful to that covenant through all the vagaries of history. …
