Yoga is definite and scientific. Yoga means union of soul and God, through step-by-step methods with specific and known results. It raises the practice of religion above the differences of dogma. My guru, Sri Yukteswar, extolled Yoga; he did not, however, indicate that realization of God thereby would be immediate. "You have to work hard for it," he told me. I did, and when the promised results came, I saw that Yoga was marvelous.
--Paramahansa Yogananda, Man's Eternal Quest