The Kriya yoga system consists of a number of levels of pranayama, mantra, and mudra based on techniques intended to rapidly accelerate spiritual development and engender a profound state of tranquility and God-communion. Yogananda attributes his description of "Kriya Yoga" to his lineage of gurus, Sri Yukteswar Giri, Lahiri Mahasaya, and Mahavatar Babaji. The latter is reported to have introduced the concept as essentially identical to the Raja Yoga of Patanjali and the concept of Yoga as described in the "Bhagavad Gita".