Instructions on Posture for Effective Meditation
One of the first requisites for meditation is correct posture. The spine should be erect. When the devotee is seeking to direct his mind and life force upward through the cerebrospinal axis to the centers of higher consciousness in the brain, he should avoid stricture or pinching of the spinal nerves caused by improper posture.
Those persons whose legs are supple may prefer to meditate sitting cross-legged on a cushion on the floor.
If the correct posture has been assumed, the body will be stable yet relaxed, so that it is easily possible to remain completely still, without moving a muscle.
Now, close your eyes and gently lift your gaze upward, without straining, to the point between the eyebrows — the seat of concentration, and of the spiritual eye of divine perception.
— Paramahansa Yogananda