20:1 Although Israel was a united kingdom, it was still made up of 12 separate tribes. These tribes often had difficulty agreeing on the goals of the nation as a whole. Tribal jealousies had originally kept Israel from completely conquering the Promised Land (read the book of Joshua), and now tribal jealousies were threatening the stability of David’s reign by giving Sheba an opportunity to rebel (20:1ff).
20:7-10 Once again Joab’s murderous act went unpunished, just as it did when he killed Abner (3:26, 27). Eventually, however, justice caught up with him (1 Kings 2:28-35). It may seem that sin and treachery often go unpunished, but God’s justice is not limited to this life’s rewards. Even if Joab had died of old age, he would have had to face the day of judgment.
20:16ff Joab’s men were attacking the city, and it looked as if it would be destroyed. Though women in that society were usually quiet in public, this woman spoke out. She stopped Joab’s attack, not with weapons, but with wise words and a plan of action. Often the courage to speak a few sensible words can prevent great disaster.
20:23 Benaiah was the captain of David’s bodyguard and a famous member of that special group of mighty men called “the thirty” (23:24). He remained loyal to David during Absalom’s rebellion. Later he helped establish Solomon as king (1 Kings 1:32-40; 2:28-34) and eventually replaced Joab as commander of Israel’s army (1 Kings 2:35).