The oldest text in Leviticus, chapter 26, has a Seven Plagues story we did not know about. That chapter has the first rule of the Hebrew returnees in 538 BCE, with a warning: if you break it, Yahweh will bring Seven Plagues on the Hebrew returnees.
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Click here to see Exodus divided into "sources" according to the Documentary Hypothesis
The podcast is written, edited and produced by Gil Kidron