Eizon ［叡尊］ (1201–1290): Also known as Eison and Shien. A restorer of the Precepts (Ritsu) school in Japan. Born in Yamato Province, he first studied the teachings of the True Word (Shingon) school at Daigo-ji temple in Kyoto. In 1224 he went to Mount Kōya, the center of the esoteric teachings, to further his study. Awakened to the importance of the Buddhist precepts and grieved at the decline of those precepts, in 1235 he went to Saidai-ji temple of the Precepts school at Nara to restore it to prominence. The following year he accepted the precepts in a self-administered ceremony at Tōdai-ji temple. He also visited various temples in the surrounding areas where he lectured on the teaching of the precepts and administered the precepts to clerics and lay believers.
In 1262, at the request of the former regent Hōjō Tokiyori and other government authorities, Eizon went east to Kamakura, the seat of the shogunate, where he and his disciple Ryōkan disseminated the teaching of the precepts. After half a year, he returned to Saidai-ji temple. Eizon won many followers among the imperial court and shogunate officials. He also undertook a number of social works. On the occasion of the Mongol invasion of Japan in 1274 and 1281, he repeatedly conducted an esoteric prayer ritual to ward off the invasion. Eizon engaged in the practice of both the precepts and the True Word teachings. He is regarded as the founder of the True Word Precepts (Shingon–Ritsu) school based at Saidai-ji temple. He was posthumously given the title Bodhisattva Kōshō (Promoter of the Correct).