In 1280, at the request of Kakushinni (the youngest daughter of Shinran, and the aunt of Nyoshin) and her son, Kakue, Sinnyo succeeded the light of Buddhism at Otani-byodo Mausoleum (which was the mauseleum of Shinran, and later became Hongan-ji Temple.)
弘安3年（1280年）、覚信尼（親鸞の末娘、如信の伯母）とその子覚恵の依頼により、大谷廟堂（親鸞の廟処。後の、本願寺）の法灯を継ぐ。