Gene who wrote the preface was one of the most educated priests pursuing his studies in those days and became Hoin (the highest rank in the hierarchy of Buddhist priests) Gon Daisozu (the second highest grade that can be held by one who has reached the second highest rank in the hierarchy of Buddhist priests) after learning Tendai Esoteric Buddhism.
序文を書いた玄慧は、天台密教を修めて法印権大僧都となった当時屈指の学僧である。