A master in Zen is not simply a teacher. In all the religions there are only teachers. They teach you about subjects which you don't know, and they ask you to believe because there is no way to bring those experiences into objective reality. Neither has the teacher known them - he has believed them; he transfers his belief to somebody else.
Zen is not a believer's world. It is not for the faithful ones; it is for those daring souls who can drop all belief, unbelief, doubt, reason, mind, and simply enter into their pure existence without boundaries. But it brings a tremendous transformation.
Hence, let me say that while others are involved in philosophies, Zen is involved in metamorphosis, in a transformation. It is authentic alchemy: it changes you from base metal into gold. But its language has to be understood, not with your reasoning and intellectual mind but with your loving heart. Or even just listening, not bothering whether it is true or not. And a moment comes suddenly that you see it, which has been eluding you your whole life. Suddenly, what Gautam Buddha called "eighty-four thousand doors" open.
Osho Zen: The Solitary Bird, Cuckoo of the Forest Chapter 6