Adapted from Kelly McGonigal (Yoga for Pain Relief):
Yoga identifies joy - a natural sense of well-being, gratitude, and peace - as the deepest aspect of what it means to be human...In the yogic view, joy is the closest to what [we] might call [our] true nature. Not a fast changing, fast disappearing happiness that fluctuates according to thoughts, mood and present circumstances...[but] an ability to feel at peace in this moment [which] is central to who [we] are...Yoga practice helps [us] reconnect to this inner joy...bringing [us] back to [our] natural sense of well-being.