Circa 778, he mastered enju-ho (literally, prayers for life prolonging) at Mt. Murou in Yamato Province and cured a chronic disease Crown Prince Yamabe (the future Emperor Kammu) was suffering from, thereby earning the profound trust of the prince.
宝亀9年（778年）頃に大和国室生山で延寿法を修して山部皇太子（後の桓武天皇）の宿痾を治したために、後に桓武天皇の深い信頼を得た。