1 Samuel 17:14

And David was the youngest; and the three eldest followed Saul.

But the Spirit of the Lord departed from Saul, now that his rejection was an established fact, and an evil spirit from the Lord, having been given permission to that effect by the Lord, troubled him, fell upon him and terrified him, filled him with anxious worry and a nameless dread. It was a wicked power, which had a strange control over him.