And he went unto his father’s house at Ophrah. — Probably, like Absalom, he seized the opportunity of some local or family feast at which all his brethren would be assembled (2 Samuel 13:23); it may even have been the anniversary of Gideon’s vision.
Slew his brethren... — This is the first mention in Scripture of the hideous custom, which is so common among all Oriental despots, of anticipating conspiracies by destroying all their brothers and near kinsmen. (Comp. Pope, Epistle to Arbuthnot: “Bear, like the Turk, no brother near the throne.”) There is little affection and much jealousy in polygamous households. Abimelech by this vile wickedness set a fatal precedent, which was followed again and again in the kingdom of Israel by Baasha (1 Kings 15:29), Zimri (1 Kings 16:11), Jehu (2 Kings 10:7), and probably by other kings (2 Kings 15); and by Athaliah (2 Kings 11:1) in the kingdom of Judah. Herod also put to death most of his kinsmen, and some of his sons (see Life of Christ, i. 43). Seneca says, “Nec regna socium ferre, nec taedae sciunt” — nor realms nor weddings admit a sharer (Agam. 259).
Threescore and ten persons. — Jotham is counted in this number.
Upon one stone. — Perhaps on the rock on which was built Gideon’s altar; at any rate, by some formal execution. How ruthlessly these murders were carried out we see from 2 Kings 10:7, and from many events in Eastern history. On one occasion, at a banquet in Damascus. Abdallah-Ebn-Ali murdered no less than ninety of the rival dynasty of the Ommiades.