The tricky thing about leadership is that while it's true the leader is "in authority", it's also true that the leader is "under authority"... God's. While King David got a lot of things right, there was something he got very wrong. Somehow, he got it in this head (heart?) that, as king, if he saw something he wanted, he could take it. This was the start of a very bad time in David's life. We should be stunned by what unfolds in this passage. We should also weep. A giant of a man is about to be felled.