Deshan Xuanjian (780/2-865; Chinese: 德山宣鑒; Wade–Giles: Te-shan Hsuan-chien; Pinyin: Déshān Xuānjiàn; Japanese: Tokusan Senkan) was a Chan master who was known for hitting his students with his staff to express awakening. Through his student Xuefeng Yicun, he is the ancestor to two of the Five Houses of Zen, the Yunmen School and the Fayan School.
Recording of Case 13 of the Wumenguan – Deshan Holds His Bowls
Deshan was a Vinaya scholar who later he became famous for his knowledge of the Diamond Sutra. While traveling the country, seeking to debate those who expounded the "special transmission outside the sutras", he was directed to the master Longtan. As result of studying under the Chan Master, he abandoned his previous beliefs and eventually burned all of his Diamond Sutra commentaries.