The following is an excerpt from the book Zen Mind, Beginner’s Mind by Shunryu Suzuki:

If you want to obtain perfect calmness in your zazen, you should not be bothered by the various images you find in your mind. Let them come, and let them go. Then they will be under control. But this policy is not so easy. It sounds easy, but it requires some special effort. How to make this kind of effort is the secret of practice.

Suppose you are sitting under some extraordinary circumstances. If you try to calm your mind you will be unable to sit, and if you try not to be disturbed, your effort will not be the right effort. The only effort that will help you is to count your breathing, or to concentrate on your inhaling and exhaling. We say concentration, but to concentrate your mind on something is not the true purpose of Zen. The true purpose is to see things as they are, to observe things as they are, and to let everything go as it goes. This is to put everything under control in its widest sense.

The true purpose is to see things as they are, to observe things as they are, and to let everything go as it goes.

Zen practice is to open up our small mind. So concentrating is just an aid to help you realise ‘big mind’, or the mind that is everything.

If you want to discover the true meaning of Zen in your everyday life, you have to understand the meaning of keeping your mind on your breathing and your body in the right posture in zazen.

You should follow the rules of practice and your study should become more subtle and careful. Only in this way can you experience the vital freedom of Zen.