Combining here.the idea of fallen angels came from Jewish sources,
"Satan, yetzer ha-ra and the angel of death are one and the same" (Baba Bathra 16a)
also read the two fallen angels Uzza and Uziel
the sons of God who mated with female humans (their children were nephilim giants)
We see the theology of John first mentioning jesus in combination with hell.(The other gospels just tell a simple story as in not occupied as to how god or religion should be percieved. Therefore John stands out and are people given the advise to read John if they want to understand what christianity is about.)
But 'Uz' in the older texts used to be one of the names for Edom.
We've discussed long ago how living in islamic and christian lands changed the writing and ideas on interpreting the old hebrew texts.
It's important to keep that in mind.