Oldest and Fatherless: The Terrible Secret of Tom Bombadil (2011)

Tolkien on Tom in Letter 144: I might put it this way. The story is cast in terms of a good side, and a bad side, beauty against ruthless ugliness, tyranny against kingship, moderated freedom with consent against compulsion that has long lost any object save mere power, and so on; but both sides in some degree, conservative or destructive, want a measure of control. but if you have, as it were taken 'a vow of poverty', renounced control, and…

I seem to be in the small minority but I always found Tom Bombadil to be one of the most curious characters in the LoTR, it's a pity he's usually edited out in adaptations. And he's no transient character either, Tolkien later wrote poems about him and he's also mentioned in The Return of the King. I don't quite buy the explanation given in this post, although it was an interesting read. I think Bombadil is beyond good and evil…

Seems unlikely. More likely, he is actually a physical manifestation of Eru, in his playful (Loki) personality.