The Dengyō Daishi zenshū 伝教大師全集 is the complete collection of the works of Dengyō Daishi Saichō 伝教大師最澄 (767–822). However, many have propounded theories stating that the Sambyōdō gi 三平等義,a work contained in this collection, was not actually authored by Saichō but was instead the work of Ennin 円仁 (794–864). But this work was in fact not written by a single author, but was put together by more than two writers.
In this paper the author of the main text, Ennin or Saichō, will be considered, focusing on the following two points. First, it is difficult to recognize this text as a work of Saichō. Second, there is a possibility that Ennin and his disciple Annen 安然 (841–889?) were both involved in the creation of this text.
Specifically, Shōshin 証真 (1124–1208) and Nichiren 日蓮 (1222–1282) paid particular attention to this text. Shōshin quotes from the text in his Hokeshō shiki 法華疏私記,and Nichiren quotes from it in the Chū hokekyō 注法華経. However, comparing the text with other works by Saichō, many terms that are not used in other works by Saichō can be found in the section that Shōshin and Nichiren focused on. Therefore it is difficult to recognize it as a work authored by Saichō. Katō 可透 (1682–1734) first stated that the work was authored by Saichō in his Dengyō Daishi Senshūroku 伝教大師撰集録.Previously the work had been said to be a work of Ennin.
Furthermore, the Sambyōdō gi was influenced by the Myopopyonhwakyongnon chachu 妙法蓮華経論子注,written by Wonhong 円弘 (7th to 8th century). Also, there is a peculiar form to the works attributed to Ennin. Works written by Annen share this characteristic. Therefore, it is possible that Ennin and Annen were involved in the creation of the Sambyōdō gi.