2 Samuel 10:9 - Ellicott's Commentary On The Whole Bible

When Joab saw. — The keen eye of this experienced general at once took in both the advantages and the danger of this disposition of the enemy. He threw his whole force between their two divisions, organising his own army in two parts, one facing the Ammonites and the other the Syrians, but each capable of supporting the other in case of need. The enemy was thus cut in two, while the Israelites formed one compact body. He himself took command of the wing facing the Syrians with the choice troops of Israel, as having the stronger enemy to meet, while he gave the rest of the forces opposing the Ammonites into the hand of his brother Abishai.