If you really want paleographic and literary answers then you need to mentally separate the old testament from the new. The Satan of the new testament is a different literary device then the devil of the old testament and much more theologically evolved, similar to the notion of hell.
In the old testament you have the vestiges of a tradition of Canaanite henotheism evolving into Jewish monotheism. Especially if you include all extant writings such as those from Qumran.
Yahweh begins as a son of El and his consort or Asherah, to the highest son of El, to a replacement for El, taking El's consort and eventually becoming a lone force. The same thing happens in a mirror image to the rest of the hosts, as they get "demoted", and eventually made into servants, with one becoming an adversary. This dichotomy eventually evolves into an answer for the question of good and evil; why is there evil? Why do bad things happen to good people?
The dichotomy takes on neo-hellenist trappings with Christianity, with a faceless supreme and a faceless antithesis. Some early Christian movements replaced Yahweh or Jehovah entirely by designating him a "branch manager" sort of god, rolling satan and jehovah into one concept; others elevated Jehovah and put a face on him by inserting an avatar (christ), and likewise inserting an anti-avatar (the antichrist), in order to move these supreme forces of good and evil to higher (or non-earthly) planes. This spawned the early arguments about whether jesus was human or simply an apparition, and whether he came into existence at the whim of God or was a part of God that always existed and simply manifest itself at a certain time in the material world. There is even the essene tradition that has been proposed as a precursor to christianity and only applied to Judaism (Hellenistic, Apocolyptic, Messianic and unconventional but still Judaism).
Those on here who share a thological interpretation will have other ideas and explanations, other conclusions, based on things they feel inside, and you will have to evaluate them personally. I am only referring to the things you can see objectively and textually.
An allegory to this is fossils you might find buried in the earth. There may be several interpretations about how they got there and what they represent, but a secular geologist will base assumptions only on the physical evidence, leaving alternate theories involving the supernatural to those who feel they have defined the supernatural. I'm showing you the layers, the fossils and the dirt, and that is all.