In his commentaries on Genshinʼs源信 （942-1017） Ōjōyōshū往生要集, Hōnen argues, on the one hand, that Genshinʼs theory of Buddhism is the same as that of Shandao善導 （613-681） and, on the other hand, that Genshinʼs nembutsu is not equal to Shandaoʼs. Previous studies have held that, in his Ōjōyōshū, Genshin adopted Shandaoʼs methods of Buddhist ritual and ceremony, but did not accept his doctrine. Ryōchū良忠 （1199-1287）, in his Ōjōyōshū- giki往生要集義記, accepts Hōnenʼs assertion that Genshinʼs theory of Buddhism depends on that of Shandao, and further reinforces Hōnenʼs interpretation. In addition, he mentions that Genshinʼs idea of nembutsu is different from that of Shandao. Therefore, Ryōchūʼs explanation of Ōjōyōshū in his treatise can be generally said to be based on Hōnenʼs interpretation.
