247) Why Pray? - James 5::14-15

Have you ever wondered why God wants us to pray? Isn't it a little arrogant for a finite, sinful human being to presume to ask God to behave a certain way? If we really trust God, wouldn't we just say, "God, you just decide whatever is best and do that. I trust whatever you decide"? Why does God want us to ask him to do specific things instead of just trusting him with the decision of what to do?