If you receive things just as an echo of yourself, you do not really see them, you do not fully accept them as they are. - Shunryu Suzuki

The most important things in our practice are our physical posture and our way of breathing. We are not so concerned about a deep understanding of Buddhism. As a philosophy, Buddhism is a very deep, wide, and firm system of thought, but Zen is not concerned about philosophical understanding. We emphasize practice. We should understand why our physical posture and breathing exercise are so important. Instead of having a deep understanding of the teaching, we need a strong confidence in our teaching, which says that originally we have Buddha nature. Our practice is based on this faith.

You see something or hear a sound, and there you have everything just as it is.
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Whatever you do, it should be an expression of the same deep activity. We should appreciate what we are doing. There is no preparation for something else.

When you are practicing zazen, do not try to stop your thinking. Let it stop by itself. If something comes into your mind, let it come in, and let it go out. It will not stay long. When you try to stop your thinking, it means you are bothered by it. Do not be bothered by anything.