A Heian-era Japanese Tendai monk and one of the nittō hakke (入唐八家) Tang-pilgrim Japanese monks. Founder of the Tendai-Jimon 天台寺門 sub-school of Japanese Tendai. Japanese name Enchin 圓珍; posthumous title Chishō Daishi 智證大師 (“Great Master of Wisdom-Verification”). Born 814 CE; died 891 CE.
He undertook his Tang study mission 853–858, visiting Cháng’ān (where he received Esoteric initiation at Qīnglóngsì 青龍寺 from Fǎquán 法全, in the lineage of Huìguǒ) as well as the Tāizhōu, Wēnzhōu, and Fúzhōu Buddhist centers. His Tang study took place after the Huìchāng persecution (845) had largely ended Tang court Buddhist patronage, making his importation one of the last major Heian importations of Tang Buddhist materials.
His five preserved importation catalogs (KR6s0116–KR6s0120) constitute the most extensive bibliographic coverage of any of the nittō hakke.
After his return to Japan in 858, he founded the Tendai-Jimon 天台寺門 (literally “Tendai Temple-Gate”) sub-school institutional center at Onjō-ji 園城寺 (popularly known as Mii-dera 三井寺) on Lake Biwa — distinct from the Tendai-Sanmon 天台山門 (literally “Tendai Mountain-Gate”) main lineage at Mount Hiei (the Enryaku-ji) under the post-Ennin successors. The Sanmon-Jimon schism became one of the principal institutional divisions within Japanese Tendai in the late-Heian and Kamakura periods, with periodic violent confrontations between the two groups of warrior-monks.
He served as the fifth zasu (Mount Hiei abbot) from 868 until 891 — but is best remembered for the Onjō-ji / Mii-dera Jimon establishment.
He was posthumously titled Chishō Daishi in 927 — making him (with Saichō = Dengyō Daishi, Ennin = Jikaku Daishi, and Kūkai = Kōbō Daishi) one of the four principal Heian daishi-titled masters.
Source: KR6s0116–KR6s0120 (Enchin’s importation catalogs); standard Japanese Heian Tendai-Jimon biographical sources.