Zazen
Zazen (坐禅) is at the heart of Zen Buddhist practice. The aim of zazen is just sitting opening the hand of thought. This is done either through koans, Rinzai's primary method, or whole-hearted sitting (shikantaza), the Soto sect's method. Once the mind is able to not be hindered by its many layers, one will then be able to realize one's true Buddha nature. In Zen Buddhism, zazen (Japanese: literally "seated meditation") is a meditative discipline practitioners perform to calm the body and the mind and experience insight into the nature of existence and thereby gain enlightenment (satori).
The posture of zazen is seated, with folded legs and hands, and an erect but settled spine. The legs are folded in one of the standard sitting styles. The hands are folded together into a simple mudra over the belly. In many practices, one breathes from the hara (the center of gravity in the belly) and the eyelids are half-lowered, the eyes being neither fully open nor shut so that the practitioner is not distracted by outside objects but at the same time is kept awake.
Long periods of zazen, usually performed in groups at a zendo (meditation hall), may alternate with periods of kinhin (walking meditation). The beginning of a zazen period is traditionally announced by ringing a bell three times (shijosho), and the end of a round by ringing the bell once (hozensho). Before and after sitting on the zafu, zen practitioners perform a gassho bow to the cushion, to fellow practitioners, and to the teacher.
In Japan, seated zazen is traditionally performed on a mat called a zabuton while sitting on a cushion called a zafu. The common positions used to sit on the zafu are:
In addition, it is not uncommon for modern practitioners to sit zazen in a chair, often with a wedge behind the lower back to help maintain the natural curve of the spine.
Very generally speaking, zazen practice is taught in one of three ways.
Shikantaza is usually associated with the Soto or “gradual” school, and koan practice with the Rinzai or “sudden” school. In reality many Zen communities use both methods depending on the teacher and students.
Concentration
The initial stages of training in zazen will usually emphasize concentration. By focusing on the breath at the hara, often aided by counting, one builds up the power of concentration, or “joriki.” In some communities or sanghas, the practice is continued in this way until there is some initial experience of Samadhi or “one-pointedness.” At this point the practitioner moves to one of the other two methods of zazen.
Koan Introspection
Having developed the power of concentration, the practitioner can now focus his or her attention on a koan as an object of meditation. Since koans are not solvable by the intellectual reasoning, koan introspection is designed to shortcut the intellectual process leading to direct realization.
Shikantaza (just sitting)
Shikantaza is objectless meditation, in which the practitioner does not use any specific object of meditation, but uses the power developed in concentration to remain completely aware of all phenomena that arises and passes in the present moment.