The Kanjin-honzon-shō (『観心本尊抄』) is now widely accepted as the masterpiece of the great importance among the doctrinal treatises written by Saint Nichiren (1222-1282). Its formal title named by Saint Nichiren himself is the Nyorai-metsugo-gogohyakusai-shi- kanjin-honzon-shō (如来滅後五五百歳始観心本尊抄) meaning “the essential of kanjin- honzon revealed for the first time for five hundred years as the beginning of the long-term decadent age in five times five hundred (two thousand and five hundred) years after the passing of the tathāgata (the Buddha).” The person having shortened the formal title to the Kanjin-honzon-shō is considered to be Toki Jyōnin(富木常忍) who received the treatise from the author. This paper examines the meaning of the word ‘kanjin-honzon’ (観心本尊) in the title of the Kanjin-honzon-shō. The conclusion is as following. Kanjin-hōmon (観心法門) meaning ‘kanjin as the gateway of Buddhist teaching leading to enlightenment’ revealed in the Kanjin-honzon-shō is the lifelong teaching of Saint Nichiren. And kanjin-hōmon is identified with sandai-hihō (三大秘法), meaning ‘the three great secret formulas’ of honzon (本尊, the principal object of worship), daimoku (題目, the title of the Lotus Sutra) and kaidan (戒壇, the site for ordaining) of honmon d(本門, the true teaching revealed in the latter half of the Lotus Sutra) as the great formula (大法) suitable for the decadent age when the Buddhist teachings have been expiring (末法). The essence or the principle of kanjin is nothing but the world view of ichinen-sanzen (一念三千) that the third power of thousands of worlds (三千) are included in a momentary mind (一念). Saint Nichiren learned and understood the theories described in the Móhē-zhĭ-guān (『魔訶止観』) written by Tiān-tái-tiān-shī (天台大師) Zhī-yĭ (智顗), and he realized the world view of ichinen-sanzen connoted in figurative passages of the Chapter of Lifespan of the Tathāgata (如来寿量品) belonging to honmon in the Lotus Sutra. And then Saint Nichiren established a practical training method (事行, jigyō) of ippi-soku-sampi(一秘即三秘) meaning that the three great secret formulas (sandai-hihō) coverge on the single great secret formula of daimoku of honmon and the single formula diverges into the three formulas. Hence, it is conceivable that the word ‘kanjin-honzon’ in the title of the Kanjin-honzon-shō has the meaning connoting sandai-hihō (the three great secret formulas), that is to say, that ‘kanjin-honzon’ has the meaning connoting not only honzon of honmon as kanjin but also daimoku of honzon as kanjin and kaidan of honzon as kanjin. In other words, kanjin-honzon is the state that sandai-hihō or the three great secret formulas are identified mutually and the whole three formulas exist. As sandai-hiho should be realistically practiced and then fulfilled, Saint Nichiren represented it as jigyō (事行), namely, ‘practical training’.
