Yahweh said to Samuel, How long will you mourn for Saul, seeing I have rejected him from being king over Israel? fill your horn with oil, and go: I will send you to Jesse the Bethlehemite; for I have provided me a king among his sons.
Actually, David had a great admiration for Saul. Of course just a young boy, and he was at that hero age, and Saul, big, tall, handsome fellow became sort of a hero in David's eyes. David always respected Saul right to his death and even after his death. David never lost his respect for this man.