Eight Limbs of Yoga - III. Asanas (Body postures)

Asana is the practice of physical postures.

It is the most commonly known aspect of yoga for those unfamiliar with the other seven limbs of Patanjali’s Yoga Sutra. The practice of moving the body into postures has widespread benefits; of these the most underlying are improved health, strength, balance and flexibility. On a deeper level the practice of asana, which means "staying" or "abiding" in Sanskrit, is used as a tool to calm the mind and move into the inner essence of being.

The challenge of poses offers the practitioner the opportunity to explore and control all aspects of their emotions, concentration, intent, faith, and unity between the physical and the ethereal body. Indeed, using asanas to challenge and open the physical body acts as a binding agent to bring one in harmony with all the unseen elements of their being, the forces that shape our lives through our responses to the physical world. Asana then becomes a way of exploring our mental attitudes and strengthening our will as we learn to release and move into the state of grace that comes from creating balance between our material world and spiritual experience.

As one practices asana it fosters a quieting of the mind, thus it becomes both a preparation for meditation and a meditation sufficient in and of itself. Releasing to the flow and inner strength that one develops brings about a profound grounding spirituality in the body.

The physicality of the yoga postures becomes a vehicle to expand the consciousness that pervades our every aspect of our body. The key to fostering this expansion of awareness and consciousness begins with the control of breath, the fourth limb – Pranayama. 

Patanjali suggests that the asana and the pranayama practices will bring about the desired state of health; the control of breath and bodily posture will harmonize the flow of energy in the organism, thus creating a fertile field for the evolution of the spirit. "This down-to-earth, flesh-and-bones practice is simply one of the most direct and expedient ways to meet yourself. …

This limb of yoga practice reattaches us to our body. In reattaching ourselves to our bodies we reattach ourselves to the responsibility of living a life guided by the undeniable wisdom of our body."viii To this B.K.S. Iyengar adds: "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 know that He is within."ix

Sources:

HolisticOnLine  http://www.holisticonline.com/Yoga/hol_yoga_home.htm
Yoga Mind, Body & Spirit, by Donna Farhi
Light On Yoga, by B.K.S. Iyengar
Yoga Mind & Body, Sivananda Yoga Vedanta Center
The Essence of Yoga, Reflections on the Yoga Sutras of Patanjali, by Bernard Bouanchaud

Notes:
Yoga Mind, Body & Spirit, by Donna Farhi, page 7.
Donna Farhi, page 9.
Light On Yoga, by B.K.S. Iyengar, page 34.
Farhi, page 11.
Iyengar, page 35.
Iyengar, page 36.
Farhi, page 15.
Farhi, page 17.
HolisticOnLine
Iyengar, page 41.
Iyengar, page 44.
HolisticOnLine
Iyengar, page 48
Iyengar, page 49
Iyengar, page 51
HolisticOnLine
Yoga Mind & Body, Sivananda Yoga Vedanta Center, page 154
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