Monotheism and the OT

The book of Genesis begins by assuming that there is only one true God, and that assumption is maintained throughout the OT. Against materialism, which teaches that matter is everything and eternal, Gen. 1 teaches that matter had a beginning and that God created it and is therefore above it. Against pantheism, which teaches that God is (or gods are) in everything, Gen. 1 teaches that God is above everything and separate from it. Against dualism, which posits a continuing struggle between two gods or principles (one evil and the other good), Gen. 1 posits one benevolent God who declares each of his creative works to be "good" and summarizes the week of creation by proclaiming it "very good" (Gen. 1:31).

But other alternatives, commonly held by ancient Near Eastern religion in general, influenced the spiritual struggles of the Hebrew people from the patriarchal period and onward. Polytheism characterized Abraham's ancestors (Josh. 24:2), kinsmen (Gen. 31:19), and descendants (Gen.35:2). Although all three biblically derived monotheistic religions claim Abraham as their founder, Abraham's monotheism was perhaps more practical than theoretical. God monopolized his allegiance to the extent that Abraham had neither room nor time for competing deities, but nowhere in Genesis does he clearly deny their existence.

By contrast, Moses defined the nature of God in a clearly monotheistic fashion (Deut. 4:35,39; 32:39). The first of the Ten Commandments, "You shall have no other gods before / besides me" (Exod. 20:3; Deut. 5:7), insists that Israel is to have only one object of faith and worship. Elijah on Mount Carmel likewise demanded that the people choose either the Lord or another god (see also Josh. 24:15), because it was both unseemly and unwise to continue to "waver between two opinions" (I Kings 18:21).

The writing prophets of the eighth century BC and afterward strengthened monotheistic doctrine by constantly reminding Israel of the vast gulf that separated the Lord from pagan idols and the so called gods that they represented (Hos. 4:12; Isa. 2:8, 20; 17:8; 31:7; Jer. 10:5,10). After Jerusalem was destroyed in 586 BC the people of Judah forsook idolatry once and for all. The excessive polytheism of Babylon was revolting to the exiles and helped to make the Jews a truly monotheistic people. Judaism today shares with Christianity a firm belief in the Lord's affirmation as mediated through Isaiah: "There is no God apart from me" (Isa. 45:21).