Tolkien saw himself and his wife as Beren and Luthien, I believe.

Some see Bombadil as God visiting his creation, others as a pre-Christian god.

Bombadil is wholly unaffected by the Ring if you recall and is able to both notice it and see thru Frodo being invisible.

Edit to add: https://www.atlasobscura.com/places/jrr-tolkiens-grave