Verses 1-6 – Have you ever tried to do something nice for someone and only got ridicule from them instead? This is what happened to David. He had no ulterior motive towards Hanun. However, Hanun listened to the advice of wicked counsel. The Israelites beards were a sign of maturity and authority to their culture, so when they were half shaved off it made them ashamed, not to mention their clothing cut out on the backside exposing their behinds. Instead of Hanun admitting he had been wrong, he decided to prepare for war against the Israelites.
Verse 12 – Although Joab said, “Let us fight bravely,” he also said, “The Lord will do what is good in his sight.” There should be a balance between our actions and our faith in God. We use our minds and our resources to obey God, while at the same time trusting God for the outcome.
Verses 15-19 – The people of Ammon weren’t as brave as they had thought. They hadn’t considered the consequences of war for the actions they had taken. The Syrians knew they were defeated also. They gathered together with the Syrians who were gathered beyond the River Jordan. David killed seven hundred charioteers and forty thousand horsemen of the Syrians. What was left of the Syrians, fled. When all the kings who were servants to Hadadezer saw they were defeated, they made peace with Israel. The Syrians were afraid to ever help the people of Ammon anymore.