Jamieson, Fausset and Brown on Nahum 3:4

4. Because of the multitude of the whoredoms--This assigns the reason for Nineveh's destruction.

of the well-favoured harlot--As Assyria was not a worshipper of the true God, "whoredoms" cannot mean, as in the case of Israel, apostasy to the worship of false gods; but, her harlot-like artifices whereby she allured neighboring states so as to subject them to herself. As the unwary are allured by the "well-favored harlot's" looks, so Israel, Judah (for example, under Ahaz, who, calling to his aid Tiglath-pileser, was made tributary by him, 2Ki 16:7-10), and other nations, were tempted by the plausible professions of Assyria, and by the lure of commerce (Re 18:2, 3), to trust her.

witchcrafts--(Is 47:9, 12). Alluding to the love incantations whereby harlots tried to dement and ensnare youths; answering to the subtle machinations whereby Assyria attracted nations to her.

selleth--deprives of their liberty; as slaves used to be sold: and in other property also sale was a usual mode of transfer. Maurer understands it of depriving nations of their freedom, and literally selling them as slaves to distant peoples (Joe 3:2, 3, 6-8). But elsewhere there is no evidence that the Assyrians did this.

families--peoples.