Sthirasukham Asanam Sutra 2.46

In Patanjali’s Yoga Sutras, asana, the third limb of the 8 limb path, has a mere 3 verses dedicated to it. (interesting that asana has popularized yoga in the past century) The first of the 3 verses states asana should have firmness/strength, sthira, and sukham, ease/relaxation. Sthira implies that one will have to utilize effort and inner strength and sukham implies that one must surrender and utilize softness and no effort. So what Patanjali is saying is that we must simultaneously reach both directions in the center to achieve a state of true asana.
Firmness and effort is needed to free the mind of distractions so that we are able to create ease and thus absorption on the infinite.
So where does pain fit in here? When we first attempt challenging poses our firmness overrides the ease. We don’t find ourselves in the center of sthira and sukham. So mind and body are unsteady to say the least. We must practice over and over again to create this balance. Sharath said, “Guruji told me if you want to do asana, do 1000 times for perfection.” So in the beginning, we really are not practicing true asana and that’s ok. We need tremendous dedication, patience and discipline to the practice to reach this level. You may have some bruises on your body or on your ego in the early stages. With practice these bruises heal and ease takes over. This allows our practice to unfold as a beautiful, meditative dance and your body becomes a dynamic, moving prayer dedicated to the infinite.