Tom Isn't God
Timothy J.

From Gandalf’s speech in Rivendell, it is obvious that he would not trust Bombadil with the ring, he would set it aside or forget about it.   If Tom Bombadil is Iluvatar (re: almighty, powerful, good being), then why is Gandalf worried about giving him the Ring? Albeit, it could be a vast clever ruse of Gandalf’s part, but that doesn’t align with Gandalf’s worries and concerns later on about losing the war, etc.

The  Istari are sent by someone, Illuvatar or Manwe or some other Valar,  Either way, Gandalf should recognize him when he sees him.