It was now spring, the time when kings go to war. David sent out the whole Israelite army under the command of Joab and his officers. They destroyed the Ammonite army and surrounded the capital city of Rabbah, but David stayed in Jerusalem.
David had told his troops, “The first soldier to kill a Jebusite will become my army commander.” And since Joab son of Zeruiah attacked first, he became commander.