2 Samuel 10:9-11

9When Joab saw that there was a battle line in front of him and another behind him, he chose some of Israel’s finest young men and lined up in formation to engage the Arameans.

10He placed the rest of the forces under the command of his brother Abishai. They lined up in formation to engage the Ammonites.

11“If the Arameans are too strong for me,” Joab said, “then you will be my help. However, if the Ammonites are too strong for you, I’ll come to help you.