God in Judaism has been conceived in a variety of ways. Traditionally, Judaism holds that Yahweh, the god of Abraham, Isaac, and Jacob and the national god of the Israelites, delivered the Israelites from slavery in Egypt, and gave them the Law of Moses at Mount Sinai as described in the Torah. Jews traditionally believe in a monotheistic conception of God (God is only one), which is both transcendent (wholly independent of, and removed from, the material universe) and immanent (involved in the material universe).

God is conceived as unique and perfect, free from all faults, deficiencies, and defects, and further held to be omnipotent, omnipresent, omniscient, and completely infinite in all of his attributes, who has no partner or equal, being the sole creator of everything in existence. In Judaism, God is never portrayed in any image. The Torah specifically forbade ascribing partners to share his singular sovereignty, as he is considered to be the absolute one without a second, indivisible, and incomparable being, who is similar to nothing and nothing is comparable to him. Thus, God is unlike anything in or of the world as to be beyond all forms of human thought and expression. The names of God used most often in the Hebrew Bible are the Tetragrammaton (Hebrew: יהוה, romanized: YHWH) and Elohim. Other names of God in traditional Judaism include El-Elyon, El Shaddai, and Shekhinah.

According to the rationalistic Jewish theology articulated by the Medieval Jewish philosopher and jurist Moses Maimonides, which later came to dominate much of official and traditional Jewish thought, God is understood as the absolute one, indivisible, and incomparable being who is the creator deity—the cause and preserver of all existence. Maimonides affirmed Avicenna's conception of God as the Supreme Being, both omnipresent and incorporeal, necessarily existing for the creation of the universe while rejecting Aristotle's conception of God as the unmoved mover, along with several of the latter's views such as denial of God as creator and affirmation of the eternity of the world. Traditional interpretations of Judaism generally emphasize that God is personal yet also transcendent and able to intervene in the world, while some modern interpretations of Judaism emphasize that God is an impersonal force or ideal rather than a supernatural being concerned with the universe.