King Nahash, the father of King Hanun, had shown kindness to King David. With the passing of King Nahash, David wanted to express his sympathy to his son. When the Israelite delegation arrived in the land of the Ammonites, the army commanders convinced King Hanun that the Israelites had come to spy out the land for the purpose of overthrowing the kingdom. So the king disgraced the Israelite delegation by shaving off half their beards and humiliating them by cutting off the backside of their garments and then sent them on their way.
When David learned of this, he arranged for the men to remain in a secluded place until their beards had grown out. Meanwhile, the Ammonites became aware of the folly of their action and feared retaliation from the Israelites so they hired over thirty thousand soldiers from neighboring countries. When the battle was over, God had enabled the Israelites to destroy seven hundred charioteers and forty thousand foot soldiers along with their commander. [Reflection based on the Bible Reference – 2 Samuel 10:1-19]