Secret Fire

The Secret Fire had a symbolic aspect, but also a physical one, though exactly what form this took is unclear - and indeed Tolkien's own view seems to have changed over time. At the time he started writing The Lord of the Rings, he seems to have imagined the Secret Fire as being literally in the heart of the world. In the very earliest drafts of the book, Gandalf suggests that the Ring could be destroyed if one were to 'find one of the Cracks of Earth in the depths of the Fiery Mountains, and drop it down into the Secret Fire' (The History of Middle-earth volume IV, The First Phase, III Of Gollum and the Ring).

Later references speak of the Secret Fire as a light that held and conveyed Ilúvatar's creative potential. One story from the most ancient times, before the Ainur descended into the world, tells of Ilúvatar granting the light as a gift to the being who would become known as Varda or Elbereth. This version of the Secret Fire would grant the power of creation to the Valar within Arda, at least in ways the followed the original themes of the Music that had created the world.

Though the Secret Fire itself was within the heart of the world, tradition said that Varda had passed a fragment of the Fire to Arien, the Maia of the Sun, so that its power could shine down upon the world. Thus Gandalf's twin claims that he was both a 'servant of the Secret Fire' and 'wielder of the Flame of Anor' (The Fellowship of the Ring II 5, The Bridge of Khazad-dûm) were directly connected to another.