First Principle of Zen

The first principle of Ch'an [Zen] practice is to empty one's mind. One must first paste the two words "life-death" on the forehead, and regard them as seriously as if one owed a debt of a million tales. In day or night, while drinking or eating, travelling or staying at home, sitting or lying, entertaining friends, in a quiet moment or at a noisy hour, you must hold on to the ... [koan]. (Zen Master Han-Shan Te-Ch'ing, in Sung-peng Hsu, A Buddhist Leader in Ming China, p. 130.)