Dahui Zonggao (J. Daie Sôkô, 1089-1163) was a Chinese Chan (J. Zen) monk of the Southern Song dynasty (1126-1279). He practiced Linji (J. Rinzai) Chan under the tutelage of Yuanwu Keqin (J. Engo Kokugon, 1063-1135). As the founder of the Dahui lineage, his sayings are collected in the three-volume Treasury of the Eye of the True Dharma (Ch. Zhengfa yancang; J. Shôbôgenzô).
The imperial court of the Song dynasty had fled to the south during the invasion by the Jin (Jurchens), but in 1127 the prime minister Qin Hui made a pact with the Jin. Because many of those who opposed Qin Hui were lay followers of Dahui, Qin Hui even directed his repressive measures against the Chan master, and Dahui was defrocked and exiled first to Hengzhou in Hunan and then to Meizhou in Canton. In 1156, he received a pardon from Emperor Gaozong (r. 1127-1163) and returned to monastic life, becoming the head monk at such places as Wanshou Temple at Mt. Jing.
Dahui sent this vibrant piece of calligraphy from his exile in Meizhou to his friend, the lay practitioner Wuxiang (J. Musô), and is the most highly valued example of Dahui's calligraphy. It was once owned by the Japanese Zen monk Kôgetsu Sôgan, who is well known as an early Edo-period tea master. Later it was owned by the famous tea master Matsudaira Fumai (1751-1818), Lord of Matsue.