Zen Mind, Beginner's Mind

When we practice zazen our mind always follows our breathing. When we inhale, the air comes into the inner world. When we exhale, the air goes out to the outer world. The inner world is limitless, and the outer world is also limitless. We say 'inner world' or'outer world' but actually there is just one world. In this limitless world, our throat is like a swinging door. The air comes in and goes out like someone passing through a swinging door. If you think, "I breathe," the "I" is extra. There is no you to say "I." What we call "I" is just a swinging door which moves when we inhale and when we exhale. It just moves; that is all. When you mind is pure and calm enough to follow this movement, there is nothing: no "I", no world, no mind nor body, just a swinging door.