The third limb of yoga is asana or posture. Asana brings steadiness, health and lightness of limb. A steady and pleasant posture produces mental equilibrium and prevents fickleness of mind. Asanas are not merely gymnastic exercises; they are postures. To perform them one needs a clean airy place, a blanket and determination, while for other systems of physical training one needs large playing fields and costly equipment. Asanas can be done alone, as the limbs of the body provide the necessary weights and counter-weights. By practising them one develops agility, balance, endurance and great vitality, Asanas have been evolved over the centuries so as to exercise every muscle, nerve and gland in the body. They secure a fine physique, which is strong and elastic without being muscle bound and they keep the body free from disease. They reduce fatigue and soothe the nerves. But their real importance lies in the way they train and discipline the mind. Many actors, acrobats, athletes, dancers, musicians and sportsmen also possess superb physiques and have great control over the body, but they lack control over the mind, the intellect and the Self. Hence they are in disharmony with themselves and one rarely comes across a balanced personality among them. They often put the body above all else. Though the yogi does not underrate his body, he does not think merely of its perfection but of his senses, mind, intellect and soul.
The yogi conquers the body by the practice of asanas and makes it a fit vehicle for the spirit. He knows that it is a necessary vehicle for the spirit. A soul without a body is like a bird deprived of its power to fly.
The yogi does not fear death, for time must take its toll of all flesh. He knows that the body is constantly changing and is affected by childhood, youth and old age. Birth and death are natural phenomena but the soul is not subject to birth and death, As a man casting off worn-out garments takes on new ones, so the dweller within the body casting aside worn out bodies enters into others that are new.
The yogi believes that his body has been given to him by the Lord not for enjoyment alone, but also for the service of his fellow men during every wakeful moment of his life. He does not consider it his property. He knows that the Lord who has given him his body will one day take it away.
By performing asanas, the sadhaka first gains health, which is not mere existence. It is not a commodity which can be purchased with money. It is an asset to be gained by sheer hard work. It is a state of complete equilibrium of body, mind and spirit. Forgetfulness of physical and mental consciousness is health. The yogi frees himself from physical disabilities and mental distractions by practising asanas. He surrenders his actions and their fruits to the Lord in the service of the world.
The yogi realises that his life and all its activities are part of the divine action in nature, manifesting and operating in the form of man. In the beating of his pulse and the rhythm of his respiration, he recognises the flow of the seasons and the throbbing of universal life. His body is a temple which houses the Divine Spark. He feels that to neglect or to deny the needs of the body and to think of it as something not divine, is to neglect and deny the universal life of which it is a part. The needs of the body are the needs of the divine spirit which lives through the body. The yogi does not look heaven-ward to find God for he knows that He is within, being known as the Antaratma (the Inner Self). He feels the kingdom of God within and without and finds that heaven lies in himself.
Where does the body end and the mind begin? Where does the mind end and the spirit begin? They cannot be divided as they are inter-related and but different aspects of the same all-pervading divine consciousness.
The yogi never neglects or mortifies the body or the mind, but cherishes both. To him the body is not an impediment to his spiritual liberation nor is it the cause of its fall, but is an instrument of attainment. He seeks a body strong as a thunderbolt, healthy and free from suffering so as to dedicate it in the service of the Lord for which it is intended. As pointed out in the Mundakopanisad the Self cannot be attained by one without strength, nor through heedlessness, nor without an aim. Just as an unbaked earthen pot dissolves in water the body soon decays. So bake it hard in the fire of yogic discipline in order to strengthen and purify it.
The names of the asanas are significant and illustrate the principle of evolution. Some are named after vegetation like the tree (vrksa) and the lotus (padma}; some after insects like the locust (salabha) and the scorpion (vrschika); some after aquatic animals and amphibians like the fish (matsya), the tortoise (kurma), the frog (bheka or manduka) or the crocodile (nakra). There are asanas called after birds like the cock (kukkuta), the heron (baka), the peacock (mayura) and the swan (hamsa). They are also named after quadrupeds like the dog (svana), the horse (vatayana), the camel (ustra) and the lion (simha). Creatures that crawl like the serpent (bhujanga) are not forgotten, nor is the human embryonic state (garbha-pinda) over- looked. Asanas are named after legendary heroes like Virabhadra and Hanuman, son of the Wind. Sages like Bharadvaja, Kapila, Vasistha and Visvamitra are remembered by having as an as named after them. Some asanas are also called after gods of the Hindu pantheon and some recall the Avataras, or incarnations of Divine Power. Whilst performing asanas the yogi's body assumes many forms resembling a variety of creatures. His mind is trained not to despise any creature, for he knows that throughout the whole gamut of creation, from the lowliest insect to the most perfect sage, there breathes the same Universal Spirit, which assumes innumerable forms. He knows that the highest form is that of the Formless. He finds unity in universality. True asana is that in which the thought of Brahman flows effortlessly and incessantly through the mind of the sadhaka.
Dualities like gain and loss, victory and defeat, fame and shame, body and mind, mind and soul vanish through mastery of the asanas, and the sadhaka then passes on to pranayama, the fourth stage in the path of yoga. In pranayama practices the nostrils, nasal passages and membranes, the windpipe, the lungs and the diaphragm are the only parts of the body which are actively involved. These alone feel the full impact of the force of prana, the breath of life. Therefore, do not seek to master pranayama in a hurry, as you are playing with life itself. By its improper practice respiratory diseases will arise and the nervous system will be shattered. By its proper practice one is freed from most diseases. Never attempt to practise pranayama alone by yourself. For it is essential to have the personal supervision of a Guru who knows the physical limitations of his pupil.