Homa, a ritual offering of clarified butter and grains to a fire, was first known from Vedic times centuries before the life of the Buddha. Not extant in the early centuries if the faith and never performed in Theravāda societies, adherents to later Mahāyāna and Vajrayāna traditions introduced it, changing some of the ritual tools and introducing religious with their philosophical doctrines. To become a member of the Newar Buddhist sangha, male vajrācāryas must be initiated and trained to perform this common practice.