When you cannot hold the body still, you cannot hold the brain still. If you do not know the silence of the body, you cannot understand the silence of the mind. Action and silence have to go together. If there is action, there must also be silence. If there is silence, there can be conscious action and not just motion.
B.K.S. IyengarSometimes our body is willing, but our mind is weak. Sometimes our mind is willing, but our body is weak. Do not be afraid. Strive to extend your capacity but do not be disappointed with yourself. What does not challenge us, cannot change us.
B.K.S. IyengarAsana is perfect firmness of body, steadiness of intelligence, and benevolence of spirit.
B.K.S. Iyengar