Witchcraft is a Mystery Religion. The first time I heard that, I thought WTF? There is nothing secretive about Neo-Paganism. You can walk into any major bookstore and find shelves filled with books on Witchcraft, and that is just a small fraction of what has been published! All you need to know is out there, available to anyone who takes the time and effort to learn it.
   
What I did not understand is that a mystery and a secret are two different things. A secret is something you can tell another person. Then they can tell someone else, and so on. All along the line everyone will know the secret. It is still the same to the last person as it is to the first one. However, a mystery cannot be told to someone. It can only be shown to them. They must experience it for themselves, leaving them forever changed in the aftermath. It is that experience that elevates us and brings true wisdom.
   
For example, love is a mystery, not a secret. You can tell another person all about being in love, but unless they have experienced it for  themselves, they will never really understand. Likewise, once a person has been in love, their world is forever altered. They will never look at their relationships the same way. I have learned that Transsexuality is the same. So is Witchcraft.
   
Eleusis in Ancient Greece was the site of a mystery rite known as the Eleusinian Mysteries. Pindar wrote that: "Blessed is he who hath seen these things before he goeth beneath the hollow earth; for he understandeth the end of mortal life, and the beginning of a new life given of Divinity." People such as Pericles, Hadrian, Marcus Aurelius, and Julian experienced the Mysteries there and and found them to be profound.
   
The Athenians, who annexed Eleusis in 600 B.C.E., had a law protecting the secrecy of the Mysteries. However, they distinguished two levels of secrecy. The Lower and Higher. The Lower Mysteries being those that could be told another person (i.e. a description of invocations, rituals, etc...). The law only applied to this. It did not forbid telling the Higher Mysteries, because they were ta arrheta, ineffable. The law recognized that it was impossible to tell another person these things. They could only be learned through personal experience.
   
It is the process - the events and how they affect the person - that is the Mystery. Not the words or gestures. You cannot tell a person wisdom. They must learn it for themselves.
   
The Eleusinian Mysteries are an example of the core dynamics of Witchcraft and Shamanism (which is what Witchcraft is at its base). That is why we do not have dogma. Why we have no converts. Neither are of any use to us. No one can be force-fed this. Witches must experience the mysteries themselves to grow as people. That is the whole point to Witchcraft. To grow, to learn, to become wise through our connection with Divinity, which is basically the world and universe we live in. It is not about believing in anything. It is about doing, about feeling, about living. To quote Joseph Campbell: "I don’t have to have faith, I have had experience."