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हठस्य प्रथमांगत्वादासनं पूर्वमुच्यते । कुर्यात्तदासनं स्थैर्यमारोग्यं चांगलाघवम् ॥१:१७॥
Hathasya prathamaangatvaadaasanam pooruamuchyate. Kuryaattadaasanam sthairyamaarogyam chaangalaaghavam.
Prior to everything, asana is spoken of as the first part of hatha yoga.
Having done asana, one attains steadiness of body and mind, freedom from disease and lightness of the limbs.
Hatha Yoga Pradipika (1:17)
Asana means a state of being in which one can remain physically and mentally steady, calm, quiet and comfortable. In the Yoga Sutras of Patanjali there is a concise definition of yogasanas: "Sthiram sukham aasanam", meaning that position which is comfortable and steady. So, we can see that yogasanas in this context are practised to develop the practitioner's ability to sit comfortably in one position for an extended length of time, as is necessary during meditation.
In raja yoga, asana refers to the sitting position, but in hatha yoga it means something more. Asanas are specific body positions which open the energy channels and psychic centres. They are tools to higher awareness and provide the stable foundation for our exploration of the body, breath, mind and beyond. The hatha yogis also found that by developing control of the body through asana, the mind is also controlled. Therefore, the practice of asana is foremost in hatha yoga.
