Blue Cliff Record

The Blue Cliff Record (Chinese: 碧巖錄; pinyin: Bìyán Lù; Japanese: 碧巌録; rōmaji: Hekiganroku; Korean: 벽암록; romaja: Byeokamrok; Vietnamese: Bích nham lục) is a collection of Chán (Zen) Buddhist koans originally compiled in China during the Song dynasty in 1125 (in the time of Emperor Huizong), and then expanded into its present form by the Chán master Yuanwu Keqin (1063–1135; Engo).

The book includes Yuanwu's annotations and commentary on 100 Verses on Old Cases (頌古百則), a compilation of 100 koans collected by Xuedou Zhongxian (980–1052; 雪竇重顯, Setcho). Xuedou selected 82 of these from the Transmission of the Lamp, with the remainder selected from the Yunmen Guanglu (雲門廣録, Extensive Record of Yunmen Wenyan, 864–949).

Yuanwu's successor, Dahui Zonggao (1089–1163), wrote many letters to lay students teaching the practice of concentrating on koans during meditation, but Dahui did not explain and analyze koans. Oral tradition holds that Dahui noticed students engaged in too much intellectual discourse on koans, and then burned the wooden blocks used to print the Blue Cliff Record to "rescue disciples from delusion".

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