I just heard the greatest story:
A man was walking on a cliff, slipped and fell, and then hung by his fingers over the edge. He hung there, and he shouted: "Help! Is there anybody up there who can help me?!"
A voice rang out like thunder: "This is God, I can help. Trust me and let go."
The man hesitated for a moment, and then shouted: "Is there anybody else up there!?"
The really funny part is that depending where you are on your spiritual development, that man will either sound really sane or really dumb.
Letting go is one of the most difficult things to learn, and one of the most important.