'Hired' in the Bible

When the Ammonites saw that they had become an object of hatred to David, they sent word and hired the Arameans (Syrians) of Beth-rehob and the Arameans of Zobah, 20,000 foot soldiers, and the king of Maacah with 1,000 men, and the men of Tob with 12,000 men [to fight for them].