You’ll have to forgive the anachronism in that last panel. The story of Daniel in the Lions’ Den wasn’t added to the scriptures until about 150 B.C., long after the time period we’re talking about. But I already did the Moses epic, Noah’s Ark, and Jonah and the Whale a couple of pages back, and the Daniel stories do still fit the theme.
You’ll also have to forgive me for compressing a much longer process into a single page. First, scriptures told stories of the other gods being Yahweh’s servants (e.g., Deuteronomy 33; Psalms 89, 103, 293). Others included the powers of other gods in Yahweh’s powers, or re-defined earlier references to gods in general (“elohim”) as referring specifically to Yahweh. Another early approach was to refer to other gods as mortal, and even dying (e.g., Psalm 82, Jeremiah 10).
Next came stories mocking gods and idols as man-made and imaginary—and mocking those who thought their gods existed (e.g., Isaiah 44-45, First Kings 18, Second Kings 19, Chronicles 32). At the same time, other stories asserted that Yahweh was the only divine being—so if you wanted, say, divination, then Yahweh was the only one who knew the future (e.g., Isaiah 40-48, Deuteronomy 4, First Kings 8).
Eventually, texts were written (or revised) to reflect a universe where other gods were simply absent. There was no need to deny them or deride them, because of course there is only the one god. Genesis 1 is a good example, but you see this all over the final version of the Old Testament.
The rhetoric of monotheism was part of a very fluid process, involving many different tactics. And it took place over many generations. And it was only one of several things driving the writing of the scriptures. (Some Old Testament scriptures were still being written when Jesus was alive!) So for me to suggest that it was a single event, reflecting a single ideology, is a godawful oversimplification. But all we need to know here is that this was a thing that happened.
Anyway, what’s more interesting (for our purposes) is what happened next.