Eison who thought that he could not live longer when he turned 85 started writing an autobiography on November 14, 1285 (old calendar) to look back at his religious belief and activities and ask disciples to look after his affairs when he died.
弘安8年（1285年）、85歳を迎えて先が短いと考えた叡尊は、自己の信仰・事業について振り返って後事を門人に託すために同年11月14日(旧暦)に執筆を開始。