In his childhood, he renounced the world to enter the priesthood and became a pupil of Kanjo-Sojo in Kyoto. After prolonged training in Buddhism at Todaiji Temple in Nara, the twenty year old Kogyo-Daishi left for Mount Koya (Kōya-san), then the center of the Shingon sect, to pursue further learning of Shingon Buddhism and its founder.
When he was thirty six, Kogyo-Daishi took leadership in the construction of the Shingon Sect. Eventually, he gathered an increasing throng of followers, attracted to his great wisdom and character and he became the chief priest of both the Daidenpoin and Kongobuji Temples. In time, he came to govern the entire religious district of Kōya-san as the Great Shingon Master. However, some in the area who harbored ill-will and envy against his great fame and power took action against him, such as setting fire to his residence, the Mitsugonin. In order to live in peace, he and his pupils moved to Negoro. After settling at Negoroji Temple he laid out his far sighted plans and began to expand the temple complex which became the head seminary for Shingi Shingon Buddhism. Kogyo-Daishi ended his significant days at the age of 49 on December 12, 1143, at Negroji, where his ashes remain buried in a tomb in the Okunoin cemetery.