Ch'an Master Yun-chu built a hut at Ch'an Master Tung-shan temple and went on a solitary retreat.

Once, Master Yun-chu had not gone to the dining hall for ten consecutive days. Hence, Master Tung-shan was concerned and also wondered what Yun-chu was doing. As a result, he sent for Master Yun-chu and asked him, "Why haven't you come to eat recently?"

Master Yun-chu said elatedly, "A deva brings me food every day!"

Upon hearing this, Tung-shan said scornfully, "I had suspected that you were only an uncultivated person who clings to worldly virtues! I'll see you tomorrow!"

The next day, Yun-chu went to see Master Tung-shan. Tung-shan loudly shouted his name. Yun-chu replied politely. Tung-shan suddenly asked, "Which is better, worldly virtues or realizing the nature of worldly virtues?"

Yun-chu was dumbfounded. Consumed with doubts, he returned to his hut. In solitude, he began to contemplate. For three days, the deva did not bring him any food. Finally, he realized the unconditional state in which he could enjoy the nourishing power of Ch'an.