Albert Barnes Commentary 2 Samuel 1:13-14

"And David said unto the young man that told him, Whence art thou? And he answered, I am the son of a sojourner, an Amalekite. And David said unto him, How wast thou not afraid to put forth thy hand to destroy Jehovah`s anointed?" — 2 Samuel 1:13-14 (ASV)

Whether or not David believed the Amalekite’s story, his anger was equally stirred, and the fact that the young man was an Amalekite did little to calm it. We know from 1 Samuel 25:13 and 25:32-34 that David had a hasty temper.