2 occurrences in 2 dictionaries

Reference: Beelzebul

Fausets

So it ought to be read in Mt 12:24; Mr 3:22; Lu 11:15, etc. The Jews, in ridicule, changed Baalzebub, the Ekronite "god of flies", into Beelzebul, "god of dung" (which however is zebel, as they changed Beth-el ("house of God") into Beth-aven ("house of vanity"), when the golden calf was set up there. Zebul means "dwelling," lord of this lower world, "prince of the power of the air" (Eph 2:2), and taking up his "dwelling" in human bodies (Mt 12:45).

Thus "master of the house" and "master of the dwelling" (Beelzebul) stand in happy contrast (Mt 10:25). As the Ekronite god was applied to by Ahaziah to east, out his disease, so the Jews taunted Jesus as using the same idol power to east out demons. Idols and demons, moreover, had a close connection (1Co 10:20-21). Beelzebul was thought to be the foul prince of both.

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Smith

Be-el'zebul

(lord of the house), the title of a heathen deity, to whom the Jews ascribed the sovereignty of the evil spirits; Satan, the prince of the devils.

Mt 10:25; 12:24; Mr 3:22; Lu 11:15

ff. The correct reading is without doubt Beelzebul, and not Beelzebub.

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