2 Samuel 10:3-7

And the princes of the children of Ammon said unto Hanun their lord, Thinkest thou that David doth honour thy father, that he hath sent comforters unto thee? hath not David rather sent his servants unto thee, to search the city, and to spy it out, and to overthrow it?

Wherefore Hanun took David’s servants, and shaved off the one half of their beards, and cut off their garments in the middle, even to their buttocks, and sent them away.

When they told it unto David, he sent to meet them, because the men were greatly ashamed: and the king said, Tarry at Jericho until your beards be grown, and then return.

And when the children of Ammon saw that they stank before David, the children of Ammon sent and hired the Syrians of Beth-rehob, and the Syrians of Zoba, twenty thousand footmen, and of king Maacah a thousand men, and of Ish-tob twelve thousand men.

And when David heard of it, he sent Joab, and all the host of the mighty men.