When Abner returned to Hebron, Joab pulled him aside to the middle of the city gate, as if to speak to him privately, and there Joab stabbed him in the stomach. So Abner died in revenge for the death of Asahel, Joab’s brother.
Previously, an Israelite man had declared, ‘Do you see this man who keeps coming out? He comes to defy Israel. The king will make the man who kills him very rich and will give him his daughter. The king will also make the family of that man’s father exempt from paying taxes in Israel.’
So Joab son of Zeruiah and David’s soldiers marched out and met them by the pool of Gibeon. The two groups took up positions on opposite sides of the pool.