Perfection in asana is reached only when the effort ceases, instilling infinite poise and allowing the finite vehicle, the body, to merge in the seer.
The sadhaka can be considered firm in his postures when persevering effort is no longer needed. In this stability, he grasps the physiology of each asana and penetrates within., reaching the minutest part of the body. Then he gains the art of relaxation, maintaining the firmness and extension of the body and consciousness. In this way he develops a sensitive mind. With this sensitivity, e trains his thinking faculty to read, study and penetrate the infinite. ?he is immersed in the boundless state of oneness which is indivisible and universal.
Some say that it is possible to acquire mastery of asana merely by surrendering to God. How can this be so? In yoga we are on a razors edge and in asana perfection must be attained through perseverance, alertness and insight. Without these we remain dull and make no progress. Surrender to God alone does not make us perfect, although it helps us to forget the stresses of life and our efforts, and guides us toward humility even when perfection in asana has been attained.
When the sadhaka has reached that state of balance, attention, extension, diffusion and relaxation take place simultaneously in body and intelligence, and they merge in the seat of the soul. This is a sign of release from the dualities of pleasure and pain, contraction and extension, heat and cold, honor and dishonour, etc
Perfection in asana brings unalloyed happiness, blessedness and beautitude.
--BKS Iyengar,
Light on the Yoga Sutras of Patanjali
