The Seven Rays is a metaphysical concept that has appeared in several religions and esoteric philosophies since at least the sixth century BCE, in both Western culture and in India. In the west, it can be seen in early western mystery traditions such as Gnosticism and the Roman Mithraic Mysteries; and in texts and iconic art of the Catholic Church as early as the Byzantine era. In India, the concept has been part of Hindu religious philosophy and scripture since at least the Vishnu Purana, dating from the post-Vedic era.