What is the nature of Satan as he is described in the Bible? in my opinion we can disregard the reference to the creature that tempted Eve in Genesis because it was merely a crafty animal:
This is reinforced in Genesis 3:14
The first mention of Satan is in 1 Chronicles 21:1
and then he is mentioned again in Job, but as an employee of God.
From where did people get the notion of Satan as he is now depicted in literature?
“Satan” is an archaic Hebrew word for “Enemy”. The Chronicles quote simply means that David faced an Enemy. In Job, OTOH, he is sPecifically referred to as “the Satan”.
I sort of figured the first from its context, so that would make Job the actual first reference to the entity “Satan” as we know him. Still, in Job he is still just an employee of God. Where does he become the ultimate bad guy we all know and love/hate?
Elaine Pagels’ The Origin of Satanmay be instructive. I don’t have my copy at hand or I would quote some relevant passages; I’ll correct that later.
About six years ago, I had a student who gave me so much crap that I started to think he might be The Horned One.
Then again, one of my colleagues claims that WalMart is the Devil.
So who knows?
I don’t know about the Old Testament Satan, but the one in the New Testament was likely a variant of the Demiurge, which comes from Platonism. When Gnosticism inherited the Demiurge (a sort of creator figure), they often made him a malevolent force. When merged with Judaism, he became the malevolent equivalent to God.
Is the Satan in the Old Testament a completely different entity from the one in the New Testament? If not, it might indicate the fall of Satan happened sometime between the Old and the New.
Or that Christianity reads the Old Testament different than Judaism does? It’s not really outrageous to say that Satan is one thing in Judaism and another in Christianity. I mean, the God of Judaism is different than the God of Christianity, so why not other figures?
Actually, I take back my previous statement. More likely, Satan is a demonized version of the Demiurge from when the gentile Christians were duking it out with the Judaic Gnostics for control over Jesus’ legacy.
This is roughly the same as Chemosh, Baal, etc. getting demonized when the various tribes of Canaan started to move towards monotheism. The tribe which won supremacy (who called their god Yahweh) incorporated and demonized the prime deity of all of the other tribes who they incorporated.
I think that the references to “Satan” in the Old Testament were no such thing at the time they were written. The Satan character was grafted on to some select passages long after the fact.
I don’t think Satan is a character in much of the Old Testament. As you point out in your OP, it’s arguable that the Serpent in the Garden of Eden should not be identified with Satan; doing so is an invention of Christianity. The Satan who appears in the Book of Job is demonstrably closer to being God’s agent than his enemy; he is clearly not exiled from Heaven, as he is reporting on his observations on Earth just as the other angels are:
This seemsw a very different character from the figure who tempted Christ during his forty-day fast.
So, in sum, the New Testament Satan is not the same character as the Old Testament one. The OT version works for Yahweh; he is humanity’s enemy only insofar as Yahweh himself is. (I’m sure some people will claim that Yahweh is unquestionably and always that – hell, I often have myself – but I’m not going to make that claim now. Sometimes the Old Testament Yahweh is malevolent; sometimes he is benevolent; frequently he is simply inscrutable.)
I’m sure Diogenes will be along shortly to school us all.
It’s also worth pointing out that of all things written in the OT, the Book of Job is perhaps the most clearly intended as a moral fable, not a history lesson. The character of the Enemy is quite potentially intended as nothing more than a literary device, and it would have been clear to the people at the time that the character was an invention of the author’s, not an otherworldly being whom people were meant to take as being part of their belief system.
I notice a resemblance between the “Satan” that tempted Job, and the “Satan” that tempted Jesus. Am I alone in this?
I haven’t read Job all the way through in a while, but I don’t recall Satan directly meeting Satan. As I remember it, the story begins with a brief explanation of who Job was, followed by God & Satan discussing him. Depending on how you read it, God either bets Satan that Job will be forever faithful, or directs Satan to test him. Satan then assails Job in various ways (destroying his property, killing his children, and finally afflicting Job with illness), but does not interact with him in a direct or conversational fashion. Job’s wife tells him to curse God and die, and Job refuses; Job then is visited by friends who offer various explanations for his sudden change of fortune; and finally Job and God talk directly, after which God restreos Job’s fortune and family. (In a sense. Even as a Christian, I was bothered by the notion that Job could see having new children as recompense for the murder of his first set.)
This is a marked contrast to the way Satan and Jesus interact. That is definitely a temptation, or rather a series of temptations. Satan and Jesus converse, and Satan tries to appeal to Jesus’s human weaknesses to move him away from his path. That seems a completely different thing that what happened in Job, in which Satan is clearly doing God’s will. In the wilderness, Satan is clearly the enemy of God and Jesus.
I dunno.
I am Spartacus.
Does that help? 
The people who wrote the New Testament had probably read the Old, so that’s not particularly miraculous.
More passages that, in my opinion, should be eliminated:
Baal was a god of the Israelites and, effectively, of the entire region East of Egypt, South of Turkey, and everything West of and including the Western half of Iraq (to use modern political geography). He was not solely a god of the Phoenicians. Chemosh, Moloch, Amurr, Yahweh, and Kaus are likely all tribal clones of Baal, hence the enmity that remains in the text. They were all competitors for the same position.
The reason that Satan has so many names (Satan, Lucifer, Samael, Baalzebub, etc.) is because they aren’t the same character. Even in the New Testament, it’s likely that most of the references to him weren’t intended to be so at the time.
So how many verses in the New Testament mention him by name, and what can we determine from them?
Then were does the popular myth spring from with regards to Satan and/or various demons having “many names”, or the ever-popular “we are legion”.
Legba, Scratch, Asmodeus, Satan, The Devil, Lucifer, Beelzebub, etc?