Yoga is not a religion. It is an ancient philosophy that is comprised of many things. One part of that is asana, or poses, which is what much of Yoga here in the west is based on, but it is important to understand that Yoga is much, much more than physical asana. Some may choose to only seek the physical benefits of Yoga, and that is OK.

Although one might be drawn to Yoga for physical reasons, while practicing asana they may notice a wonderful "feeling" during and after classes. Below is an attempt to explain what is happening, but please know, there is so much more to it than my brief answer below. There is also the physiological and scientific explanation as well, but that would be another web page, or hours and maybe a lifetime of study.

I believe, based on my experience and studies, that spirituality is what naturally arises when we bring our awareness inward rather than outward. When we stop being "external" worrying about what is "outside" - material things, what people think about us, how we are "supposed" to behave, to look. Instead, when we focus our awareness inward (as what happens when we practice Yoga) we let go the "outside" influences and we give our mind and consciousness space. We let go stress. We begin to see our Self. We start to learn who we are, and we focus on the moment and our actions in that moment. We realize how our thoughts, actions and choices affect our lives. THEN we begin to live a more "spiritual" existence, bringing balance into our lives. When there is balance there is less illness, less sadness, less anxiety, less stress and less agitation.
Kerry