It is important to understand the different aspects of the zazen posture so as not to force the body into an attitude of rigidity and stiffness which is contrary to our natural physiology. In the zazen posture there is both balance and relaxation within uprightness.,
One important aspect is the position of the pelvis. It is advised that we sit in the middle of the zafu (the round cushion, the thickness of which depends on the flexibility and height of each person), or towards the front, on the sitting bones, so that we sit stable with our sitting bones on our cushion, and our two knees on the ground. If possible, the legs should be in the lotus, or half-lotus, position.
Correct positioning of the pelvis and adjustment of the thickness of the zafu will allow the spine to rise towards the sky without creating tension in the muscles that flank your spine (tension here, can create detrimental tightness and compression). The head is in a neutral position, the shoulders, rib cage, abdomen are allowed to relax to allow you to breath freely and easily. The eyes are half-closed, with your gaze falling in front of you at an angle of approximately 45°.
The wrists are resting in your lap, on your upper thighs. The fingers of the left hand are placed on those of the right hand, palms facing upwards, thumbs meeting together, horizontally, above the palms, lightly touching to form an oval shape. The sides of the hands and the little fingers make contact with the lower abdomen.
During zazen, we remain vigilant, allowing an open attention to each detail as well as on our breathing. The mind is thus brought back into the body and unity is realised. Thoughts stop flowing together. They appear, since that is their nature, but if attention is maintained on the posture, they disappear without a trace. Naturally and unconsciously the personal will of the ego ceases to act and seek a goal. Only the present moment remains.
It is impossible to see your own posture and it is easy to delude yourself about your own practice. It is recommended not to practice alone and to receive advice from an experienced practitioner in a dojo (“the place of the Way”).