In a letter written by MINAMOTO no Yoritomo addressed to Yasutsune, there was a phrase saying, 'The greatest Tengu in Japan cannot be anyone else,' which became established as an expression used by Yoritomo's to criticize the Retired Emperor Goshirakawa and, consequently, was often quoted to describe that retired emperor.
源頼朝が泰経に宛てた書状の中で「日本第一の大天狗は余人の事に非ず候か」との表現があり、従来これは頼朝が後白河院を批判した語句であるとして、後白河院を形容する際に用いられることが多かった。