Joab, a Hebrew warrior, "captain of the host" (generalissimo of the army) during the greater part of David's reign, died about 1015 B. C. In the reign of Saul he accompanied David on his wanderings in the southern part of Palestine and its vicinitv, and after Saul's death he defeated the troops of Abner, who supported Ishbo-sheth, the son of that king, as successor, and whom he assassinated after he became reconciled to David. His valor in the assault on the fortress of Zion, held by the Jebusites, gained him the chief command of the army of all Israel, and he had the principal merit in the conquests of his master. He adhered faithfully to the king during the revolt of Absalom. When, in order to conciliate the powerful rebellious party, the command of the host was given to Amasa, who had been Absalom's general, Joab soon rid himself of this rival by murdering him. David was obliged to overlook the murders of Abner and Amasa, but before dying gave strict directions to his son Solomon to put Joab to death. Shortly before the death of David he participated in the unsuccessful demonstration in favor of the natural heir Adonijah, and afterward fled for refuge to the altar, where he was put to death by command of the new king.
His brothers Abishai and Asahel were also conspicuous as military leaders in the earlier part of the history of David.