2 Samuel 5:13
13. David took him more concubines and wives—In this conduct David transgressed an express law, which forbade the king of Israel to multiply wives unto himself (De 17:17).
2Sa 5:17-25. HE SMITES THE PHILISTINES.
1 Kings 11:3
3. he had seven hundred wives, princesses—They were, probably, according to an existing custom, the daughters of tributary chiefs, given as hostages for good conduct of their fathers.
concubines—were legitimate, but lower or secondary wives. These the chief or first wife regards without the smallest jealousy or regret, as they look up to her with feelings of respectful submission. Solomon's wives became numerous, not all at once, but gradually. Even at an early period his taste for Oriental show seems to have led to the establishment of a considerable harem (So 6:8). Song of Solomon 6:8
8. threescore—indefinite number, as in So 3:7. Not queens, &c., of Solomon, but witnesses of the espousals, rulers of the earth contrasted with the saints, who, though many, are but "one" bride (Isa 52:15; Lu 22:25, 26; Joh 17:21; 1Co 10:17). The one Bride is contrasted with the many wives whom Eastern kings had in violation of the marriage law (1Ki 11:1-3).