Satan was transliterated (as opposed to translated) from the hebrew word Saw-tan and meant accuser like a prosecuting attorney. Book of Job is an excellent read along these lines as "Satan" (the Saw-tan) served as a kind of defender of God's interest. Saw-tan served among/with the Elohim (translated god but a plural term, OT has it's own polytheism) in judging/ruling over mankind. It's also worth noting that seems to me in my reading that The Saw-tan could do nothing to Job unless God first authorized it.
Another interesting example is in the OT where God is called Satan.
And the same event recorded in Chronicles.
Now if you understand the hebrew word as meaning accuser as in prosecutor, this use of the word Satan (Saw-Tan) makes sense. It should however be said that if you accept a Genesis creation/creator POV, God could be Satan or the source of evil as God himself created it in the first place. Reconciling that requires IMO a
deep plunge into gnosticism studying the
Demiurge and Yaldabaoth and that is a deep, deep study in and of itself.
In the greek NT, Jesus in the wilderness temptation was tempted in a similar manner as the greek word diabolos translated devil meaning accuser. Literalist christianity sees the tempter in anthropomorphic form as a kind of evil god in the devil but I always liked the gnostic or esoteric tradition that Jesus was tempted by the accuser that is his own human ego.
From a christian perspective, it proves Jesus humanity and serves as example for us to place ourselves in Jesus sandals just to see how we would do when forced to face our own ego, our own will. How would we answer that temptation of "bow down to me and I give you command of the world" coming from within ourselves? How you answer determines if you enter your own spiritual Kingdom of Heaven or descend into your own spiritual hell. Tree of Life or Tree of Death.
The pagans, as opposed to orthodoxy, in their
Kundalini ideal often expressed this form most interesting IMO. Makes you wonder what that shaft with the serpent on it that Moses had really was? Metaphor? What was therefore the serpent in the Garden of Eden or for that matter the tree of life?
The irony of the garden is that the serpent told Eve the truth that if she took of the fruit she would not die and in fact she nor Adam did die. When you see the garden story as metaphor, you can look well beyond the exoteric and enjoy and appreciate the esoteric.
When you delve into comparative religions, you get to go off into the really deep part of the pool!