Yoga, an ancient but perfect science, deals with the evolution of humanity. This evolution includes all aspects of one's being, from bodily health to self-realization.
B.K.S. IyengarAbhyasa (practice) is a dedicated, unswerving, constant, and vigilant search into a chosen subject pursued against all odds in the face of repeated failures, for indefinitely long periods of time.
B.K.S. IyengarSavasana is being without was, being without will be. It is being without anyone who is.
B.K.S. IyengarYes, flexibility of body and physical perfection for Yogasana is important. However more important is the state of your mind, Meditative mind. Your flexibility might be excellent but if your mind is not attentive, you are merely doing some physical exercise, not Yoga.
B.K.S. IyengarWhenever asana is done mechanically from the front brain, the action is felt only on the peripheral body, and there is no inner sensation, there is no luminous inner light. If the asana is done with continual reference to the back of the brain, there is a reaction to each action, and there is sensitivity. Then life is not only dynamic, but it is also electrified with life force.
B.K.S. Iyengar