2SA 11:1

1 [In that region], kings usually went [with their armies] to fight [their enemies] in the springtime. But the following year, in the springtime, David [did not do that. Instead, he] stayed in Jerusalem, and he sent [his commander] Joab [to lead the army]. So Joab went with the other officers and the rest of the Israeli army. They [crossed the Jordan River and] defeated the army of the Ammon people-group. Then they surrounded [their capital city,] Rabbah.