I don’t know if you have observed this, but if you pay attention you will see something in the Old Testament: the authors and people of the OT at times seem to believe there are other gods. In chp 3 of Gerald McDermott’s God’s Rivals we find an examination of the OT and the “real existence of other gods.”

Assuming this is a fair summary, what does it say about other religions? about God’s rivals? about the scandal of particularity?
The chp contains one of the finest brief surveys of the “divine council” of the OT, the hosts of YHWH who seem to attend to God and even oppose God.
This chp contains lots of details, even if eminently clear, and there is no need even to begin trotting out too much evidence. But McDermott argues that texts like “all gods bow down before him” (Ps 97:7) do not indicate what many Christians today think. (Check out Deut 32:8-9 or 1 Kings 11:33).
After a lengthy survey of the Divine Council in the OT (e.g., Ps 89:5-8), McDermott contends the OT contains four views of the religions:
1. Some neighborly pluralism: there are some real gods; they are subordinate to YHWH; we can get along as long as they leave us alone.
2. Competitive pluralism: the gods of others rebelled against YHWH and are not worthy of honor.
3. Vehement missionary exclusivism: others are devoted to gods who are not really gods.
4. Cosmic war: religions are communities animated by powers hostile to YHWH.
These models of response are not mutually exclusive; and there is evidence in the OT for progression of thinking about the religions of others.