Many Lord of the Rings fans also say Tom Bombadil is actually the most powerful character in all of Middle Earth, due to his apparent immortality, ability to completely resist the Ring, power over his domain, and knowledge that comes from living since the beginning of time.
Tom Bombadill
He is said to be the 'oldest in existance,' and impossible to imprison. He could resist the Ring, was able to see others who were wearing it (such as Frodo), and could even wear it himself without succumbing to its power. He was able to make it disappear into thin air and reappear in his hand.
14 Tom Bombadil, The Joyful
He is a joyful soul, and this hides an immense well of power. No earthly strife seems to trouble him, and he is immune to the power of the Ring. Such propensity aligns Tom with the Valar or perhaps something greater, and Gandalf would never be able to overpower him.
More powerful than Gandalf and more ancient than Galadriel, Tom Bombadil is actually Lord of the Rings' most powerful being. When it comes to powerful beings in The Lord of the Rings, characters such as Gandalf, Saruman, Galadriel and Sauron are discussed at great length.
Sauron's desire was to dominate all life in Middle-Earth. Bombadil's desire was to be Tom Bombadil, sing his songs, and love Goldberry. Sauron's ring had no power over Bombadil, while he himself ultimately lost all his power. In his way, he was vastly more powerful than Tom Bombadil.
God is the most powerful entity in Tolkien's Lord of the Rings universe. The Elvish name for him is actually Eru Ilúvatar, meaning “the one, father of all.” So the question becomes: Who is the second-most powerful being? Originally, it was Melkor, “he who arises in might,” the most powerful of the Ainur (or angels).
As he is an ancient spirit tied to the woodland and the acorns and the leaves, it would make sense that he is only able to exist when he is near them. It also explains why he can't take the ring to Mordor and destroy it himself, because he is encased within his borders, and cannot step outside them.
Given these bits of information, it seems like within his realm, Bombadil would have been able to defeat the Nazgûl or at least banish them. Outside his realm, however, he wouldn't have been quite as effective in a fight against them.
When Frodo shows Tom Bombadil the Ring, he amazes the Hobbits by putting the Ring on without disappearing. The reason that Tom Bombadil is not subject to the power of the Ring is that he really, truly does not desire power or ownership over any one thing.
The Tolkien scholar and philosopher Gene Hargrove argued in Mythlore in 1986 that Tolkien understood who Bombadil is, but purposefully made him enigmatic. Nevertheless, Tolkien left clues that Bombadil is a Vala, a god of Middle-Earth, specifically Aulë, the archangelic demigod who created the dwarves.
Sauron would have destroyed Tom Bombadil, no question asked. Tom Bombadil is not “impervious” to Sauron power, he is not immune to violence and physical power, he is immune to the corruption of the rings and other matters of domination. This is an element of nature not of power.
While in many ways, Morgoth wins this pole, he is, however, still not the strongest. In Tolkien's lore, the most powerful being is Eru Ilúvatar, which means "the one, father of all” in Elvish.
Through all of Tolkien's extensive legendarium, the nature, purpose, and history of Tom Bombadil remains almost entirely unknown. Nevertheless, the mysterious Tom Bombadil is one of few characters from The Lord of the Rings old enough to appear in The Rings of Power.
No, Tom Bombadil could not have defeated Sauron. As Gandalf mentioned, Tom could not use the Ring's power - rather the Ring did not affect him. 'It seems that he has a power even over the Ring.
Originally Answered: Why doesn't Sauron fear Tom Bombadil? Because Tom's power is limited to the area close to his home, in and near the Old Forest. The Elves of Rivendell speculate whether he could defy Sauron, and in their opinion, he could not.
No. That's nearly impossible for a number of reasons. (1) We know that the Blue Wizards came to Middle-earth at some point in the Third Age* to help the Free Peoples in their fight against Sauron with their powers and wise counsel. Tom Bombadil lived in Middle-earth since its foundation—both he and others explain that.
Sweitzer Tom Bombadil is intriguing because he exists outside of the temporal problems of Middle Earth. It's not so much that he doesn't belong, it's just that he's so immortal and so much a part of the land itself that he exists apart from society.
Peter Jackson has explained his decision to omit Tom Bombadil from The Lord of the Rings movie trilogy, claiming that the character's contribution to The Fellowship of the Ring bore little relevance to the overall plot and did nothing to advance the main story - unlike Lord of the Rings' Istari, to which Tom Bombadil ...
There's no shame in this (despite what some hardcore corners of the fandom say), but it does leave these movie-only Middle-Earth fans vulnerable to misconceptions about Tom Bombadil's power. He is incredibly powerful and is immune to the effects of the One Ring. He is not, however, more powerful than Morgoth.
Beginning as early as Issac and Zimbardo's Tolkien and His Critics, published in 1968, Tom Bombadil has almost universally been regarded as a nature spirit.
Tom Bombadil is the oldest, as are other Maiar and Varda listed above. The Ents came from the thoughts of Yvanna (a Varda), who is the same age as Tom Bombadil.
In light of that, Sauron would have been able to defeat Morgoth at the height of his power when Morgoth was at his lowest. However, when they were both at their best, Morgoth would have utterly destroyed Sauron.
Bombadil could have been created as a side-effect of the Music of the Ainur and that would explain why he was there in the beginning. His Elvish name "Eldest Fatherless" can support this notion: since he is only a part of creation, he has no "father", while the Ainur have (Eru).
Tom is uninterested in the affairs of the ring or the world outside the Old Forest. He would not seek to stand against Sauron whether or not he lurked around the Old Forest's borders or not.
Tom's absent mindedness might lead to a forgetting of the cosmos with catastrophic consequences. As Gandalf says of Bombadil at the Council of Elrond, “If he were given the Ring, he would soon forget it, or most likely throw it away. Such things have no hold on his mind.