The book invokes the pagan notion of a pantheon of gods, rather than the Judeo-Christian God. He describes a ritual where he propitiates the Muses (the gods of creativity) before sitting down to write. You might find it easier to swallow, because when people invoke the J-C God they often mean it completely literally, while the Muses are clearly allegorical.

But to get through the book, you have to suspend your rational empiricism quite a few times. Perhaps no more than to read The Odyssey or Macbeth, where internal human struggles are illustrated with supernatural imagery.