Thematic Bible: Sent joab against the armies of, hired by the ammonites

And when the children of Ammon saw that they stank unto David, they sent and hired the sons of Bethrehob of the Syrians of Zobah: twenty thousand footmen; and of king Maacah: a thousand men; and of Ishtob: twelve thousand men. And when David heard of it, he sent Joab and all the host of strong men. And the children of Ammon came out and waged battle before the gate, and the Syrians of Zobah, of Rehob, Ishtob and Maacah were by themselves in the fields. read more.
When Joab saw that the front of the battle was before and after, he chose of all the best of Israel and put them in array against the Syrians. And the rest of the people he delivered in the hand of Abishai his brother, which put them in array against the children of Ammon. And he said, "If the Syrians overcome me, then succor me. But if the children of Ammon be too good for thee, I will come and succor thee. Quite thee like a man, and let us fight lustily for our people and for the cities of our God. And the LORD do what seemeth best in his eyes." And forthwith Joab proceeded, and the people that was with him, into battle against the Syrians: which fled before him. And when the children of Ammon saw that the Syrians were fled, then fled they also before Abishai, and entered into the city. And so Joab returned from the children of Ammon and came to Jerusalem.