Of the Heart

It is likely that the Amalekite knows that David is the next in line for the throne. While the Philistines are no doubt about to settle into Israel, David is the man who took down Goliath. David is the man who has defended Israel from invaders even while Saul was still king, and Saul hated David! Saul feared David! So it is likely that this Amalekite believes the hatred is reciprocated. This man likely thinks that he can receive a reward from the new, up-and-coming king. He just did him a favor, and has a crown and armband to prove it - he “killed” Saul! His reward is not what he expects though...