As OP notes, the New Testament's Βεελζεβούλ [Beelzebul] appears to come -- somehow -- from the Hebrew Bible's (Christian Old Testament's) בַּעַל זְבוּב [baʿal zĕbûb], "Lord of the flies".a Two specific questions are posed:
- Is Beelzeboul a term derived from the Hebrew Bible, and if so how?
The short answer is yes, errr, probably -- but the "how" takes a bit longer.
As Ted Lewis writes in the Anchor Bible Dictionary, having noted the NT occurrences: "Scholars have been fascinated with trying to find an etymology for this preeminent satanic being".1
There have been a welter of suggestions.2 A number of these have had only minimal support, and I won't report these below; there are two which have attracted the most sustained and widespread ... support, if not acceptance:
The HB/OT references for baʿal zĕbûb are given in the HALOT entry cited in the question, but for convenience they are: 2 Kgs 1:2, 3, 6, and 16 -- so four times in one chapter. And that's it for the HB/OT.
The translation tradition into Greek (and Syriac) knows both the -ub (Aquila) and -ul (Symmachus) versions beside the LXX's own Βααλ μυῖαν.3 When texts from ancient Ugarit were found with a reading of zbl bʿl, = "Baal" plus epithet, "Exalted Baal" or the like, then the suggestion seemed almost irresistible that the HB/OT's zebub was a denigrating substitution for zebul (cf. HALOT, sub זְבֻל II, "lofty"). An analogy might be in the substitution of ~boshet (= "shame") for ~baal in, e.g., the name "Ishbosheth" (compare NASB and NRSV at 2 Samuel 2:8).
The second suggestion ignores the zebub connection, in preference to finding a solution wholly from the HB/OT's zebul references (1 Kgs 8:13; Ps 49:15; Isa 63:15; Hab 3:11). Here, the connection is simply "Lord of Heaven", and the -ub version arises by false assimilation to the 2 Kings 1 text.
As I say, there are other explanations, but these two (or variations) are the leading contenders.
- Are there extra-biblical examples of Beelzeboul used as a synonym for Satan?
Only in the ~ούλ form. According to W. Foerster,4 it is found in Origen, Contra Celsum, VIII.25; and Hippolytus, Refutatio Omnium Haeresium, VI.34.1; also in the Testament of Solomon -- although in the latter it might not be used of Satan.5
For further reading see the helpful article by E.C.B. MacLaurin, "Beelzeboul", Novum Testamentum 20/2 (1978): 156-160.
Notes
a Note that "Baal" (or East Semitic bēl) is "lord", not "god". As it happens, Josephus, Antiquities, IX.19 has τὸν Ακκαρων θεὸν μυῖαν = "the Fly-God of Akkaron" - see Thackeray's edition (linked) for details.
- T.J. Lewis, "Beelzebul", in The Anchor Bible Dictionary, gen. ed. David Noel Freedman (Doubleday, 1992), vol. 1, pp. 638-40.
- Most of what follows comes from Lewis, but pared down to essentials. See also W. Herrmann, "Baal Zebub", in Dictionary of Deities and Demons in the Bible ed. by K. van der Toorn et al (2nd edn; Brill, 1999), pp. 154-156. There is a good deal of overlap between the two articles.
- Citations most readily seen in Frederick Field, Origenis Hexaplorum... (2 vols; 1875), vol. 1, p. 651 (= ad loc).
- W. Foerster, "Βεελζεβούλ", in Theological Dictionary of the New Testament, ed. by G. Kittel (Eedrmans, 1964), vol. 1, pp. 605-6.
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