1 Chronicles 19:2

And David said, either in his councilor in deliberating the matter with himself, I will show kindness unto Hanun, the son of Nahash, because his father showed kindness to me, at some time during David's exile, while Saul was seeking his life. And David sent messengers to comfort him concerning his father, to express the cordial sympathy of a neighboring ruler, as custom required. So the servants of David, his official ambassadors, came into the land of the children of Ammon to Hanun to comfort him, to transmit David's message of condolence to him.