Tendai school ［天台宗］ ( Tendai-shū): Also known as the Tendai Lotus school or the Tendai Hokke school. The Japanese counterpart of the Chinese T’ien-t’ai ( Tendai) school, founded in the early ninth century by Dengyō, also known as Saichō. Its head temple is Enryaku-ji on Mount Hiei. The basic teaching of the school consists of two aspects, doctrine and meditation. The Tendai school reveres the Lotus Sutra, ranking it above all other sutras based on T’ien-t’ai’s system of classification called the five periods and eight teachings. The school also teaches the principle of the unification of the three truths and that of three thousand realms in a single moment of life, which clarify the universality of the Buddha nature. The way to attain Buddhahood, it holds, is the practice of the meditation to observe one’s mind and see those principles in it.
The writings of the T’ien-t’ai school were brought to Japan from China in 753 by the priest Chien-chen known in Japan as Ganjin, but not until the time of Dengyō was the school formally established. In 804 Dengyō journeyed to China, where he studied the T’ien-t’ai teachings under Tao-sui and Hsing-man. He returned to Japan in 805 and in the following year obtained imperial permission to admit two government-sponsored priest candidates annually to his school. This is regarded as the founding of the Tendai school. Dengyō also petitioned the emperor for permission to build a Mahayana ordination center on Mount Hiei, but for years his request was not granted because of opposition from the priests of Nara. On the eleventh day of the sixth month, 822, seven days after Dengyō’s death, permission was finally given, and the ordination center was completed in the fifth month of 827 by his disciple and successor, Gishin.
Jikaku and Chishō, respectively the third and fifth chief priests of Enryaku-ji, incorporated teachings of Esoteric Buddhism into the doctrines of the Tendai school. Hence the Tendai school in Japan rapidly assumed the character of Esoteric Buddhism, differing in this respect from the Chinese T’ien-t’ai school. The esoteric teachings of the Tendai school are called Tendai Esotericism to distinguish them from those of the True Word (Shingon) school. While Tendai Esotericism divided into what are known as thirteen schools, the orthodox Tendai teaching also split into the Eshin school and the Danna school. The former is in the lineage of Genshin, also called Eshin. The latter is in the lineage of Kakuun. Both were disciples of Ryōgen, the eighteenth chief priest of Enryaku-ji. Later these two schools each split into four branches.
In 993 a schism finally occurred in the school between priests who followed the lineage of Jikaku and those of Chishō’s lineage. Ryōgen from Jikaku’s line had occupied the post of chief priest of Enryaku-ji for twenty years and then his disciple Jinzen succeeded him. When Yokei from Chishō’s lineage was appointed chief priest, following Jinzen, those of the rival faction fiercely opposed him. Yokei was forced to resign from the post. Thus the disciples in Chishō’s line left Mount Hiei and based themselves at Onjō-ji temple. The Onjō-ji branch became known as the Temple (Jimon) school, while the group at Mount Hiei was called the Mountain (Sammon) school. Along with the True Word school, the Tendai school was one of the dominant Buddhist schools of the Heian period (794–1185). See also Dengyō; Ryōgen; T’ien-t’ai school; Yokei.