Zazen posture is a balance between using your body’s physiology to relax and focus. Zazen is practiced while seated on a round cushion known as a zafu. The positions of the pelvic and hip bones are key. The correct balance is achieved when sitting on the middle of the zafu with both knees planted firmly on the floor.
Zazen and duality
Posture is about obtaining the right state of mind. Merging the mind and body
The legs are placed in either lotus, half lotus, or another position.
The correct position of the pelvic bone and the right zafu allows the spinal cord the space to stretch upwards without causing tension in the back and spine. Your head should be relaxed and straight, but not tense. Your breath should be unimpeded, natural; the shoulders, the rib cage, and the inner organs are also relaxed. Soft gaze with the eyes, lowered down at 45 degrees. Almost think of your eyes as being half open, half closed.
The goal of zazen is to create a unification of the mind and body. Paying attention to every detail of the breath as well as the posture. This can be characterized as the oneness of duality, body and mind are one. Focusing on posture also helps thoughts disappear as they arise in your mind. Through this practice, the ego will slowly become inactive as it relaxes and stops searching for a goal during these quiet moments.