To answer my own question about whether Satan came from Seth, according to
the "Dictionary of Deities and Demons in the Bible" (K. Van Der Toorn, B.
Becking, P. Van Der Horst), it seems that Satan does not come from Seth.
Among other things, the entry on Satan says that the root "STN" is not
evidenced in any of the cognate languages in texts that are prior or
contemporary with its occurances in the Hebrew Bible... the meaning of the
noun "satan" must be determined solely on the basis of its occurances in the
Hebrew Bible, where it occurs in nine contexts. In five it refers to human
beings, in four to celestial beings. When used of human beings it is not a
proper name but rather a common noun meaning 'adversary', either in a
polemical or a military sense, or 'accuser' when it is used in a legal
context. In the celestial realm there is only one instance where 'satan'
might be a proper name. In the other three contexts it is a noun meaning
'adversary' or 'accuser'. ..
Although the noun 'satan' has no cognates in texts that are prior to or
contemporary with the biblical texts in which is occurs, there are in
Akkadian three legal terms meaning 'accuser' that can have both terrestrial
and celestial referents. These terms are 'bel dababi', 'bel dini', and 'akil
karsi'. Each can refer to a human legal opponent or to a deity acting as an
accuser in a legal context and this each term functionally parallels the
noun satan even though there is no etymological realtionship...... Standing
behind the idea of deities assuming legal roles with respect to earthly
happenings is the well known idea of the divine council acting as a
The noun satan is used of a divine being in four contexts in the Heb
bible... as a celestial messenger of God the 'mal'ak yhwh', described as a
'satan'.... This heavenly being who acts as a 'satan' in Numbers 22 has very
little in common with later conceptualisatings of Satan. He is Yahweh's
messenger, not his archenemy and acts in accordance with Yahweh's will
rather than opposing it. Indeed, Yahweh's messenger here, as elsewhere in
the Heb bible is basically a hypostatisation of the deity, hence... the real
satan / adversary in Numbers 22 is none other than Yahweh himself.
Later on in Job we have the satan challenging Yahweh about Job's piety...
then more examples, blardy blah... Then I look up the entry on Seth, no
mention of being related to satan... more interested in talking about red
hippopotami,.. Seth is identified with Baal... Teshub... Typhon... perhaps
the confrontation between Yahweh and Behemoth is patterned upon Horus and
Seth... tentative parallel between Behemoth and Seth...
And, no - indeed it seems from consulting only one book (feel free to
correct me on this from other sources) that Seth is not related to Satan at
all. (Why did I ever think he might have been? Shrug, I dunno. Must have
been that whole "Set is more authentic than the Church of Satan's "Satan"
that I heard from TOS members many years ago... I think I must have thought
that the two figures were related, way back...)