: I think that's exactly it, Bombadil can't be measured according to the same rules as Sauron or Gandalf because he didn't have the same type of power. He renounced power over other things, and therefore nothing had power over him. However, that brings to mind an interesting question--since he obviously had power over Old Man Willow and the barrow-wight, could those things have had power over him?

Did he renounce power over things? If you read the chapters in LOTR again concerning Bombadil I think it implies that he has immense power within certain territorial bounderies and the Willow-man and Wights were in those territorial boundaries. When he escorts the Hobbits part way to Bree I think he says that he will only travel with them to the boundaries of his land and no further.

TreeBeard..........