So Hanun seized David's men, shaved off half of each man's beard, cut off their garments in the middle of the buttocks and sent them away. 2 Samuel 10:4
New leaders should always be careful about the advice they choose to follow. Hanun was the new king of the Ammonites, and he had a great deal to learn about who he should trust and who he shouldn't. His father and David apparently had a cordial relationship. His own relationship with Israel, however, wouldn't be as nice.
Following the death of Hanun's father, David sent an entourage to pay his respects. Unfortunately, those David sent as an act of kindness, returned humiliated as suspected spies. Hanun had listened to the advice of his nobles who suggested that David's men were there under false pretense - that their real intention was to spy out the land in order to overthrow it.
There is an important lesson here. If a mighty king sends a group of men to you to express kindness, be careful about questioning his motive. Regardless of his original intent, treating his delegation with contempt will most certainly determine his future treatment of you.
Lord, help me to make wise choices when I am given opportunities for new alliances. Give me the ability to weed out the bad advice, so I don't bring a bad situation from good.