Zen Master Shen Tsan gained his enlightenment through Pai Chang. He then returned to the monastery in which he had been ordained by his “first teacher,” the monk who had brought him up from childhood and who, at that time, was a very old man.

One day Shen Tsan was helping his old teacher to bathe. While washing the old man’s back, he said to him, “This is such a fine temple, but the buddha in it is not at all holy!” His old teacher then turned round and looked at him, whereupon Shen Tsan commented, “Though the buddha is not holy, he can still radiate the light.”

Again, one day, while the old man was reading a sutra near a paper-covered window, a bee tried desperately, with all its strength, to fly out of the room through the paper but was unable to get through. Shen Tsan, seeing this, said, “The world is so vast and wide that you may easily set yourself free in it. Why, then, do you foolishly bore into old, rotten paper?”

“While the empty door is open wide
How foolish it is to try and get out
By thrusting against the window!
Alas! How can you, Master,
Raise your head above the slough
By putting your nose against old, rotten paper
For a hundred years?”

Hearing this remark, the old man laid down his book and said to Shen Tsan, “For quite a few times now, you have made unusual remarks. From whom did you gain your knowledge while you were away from home?”
Shen Tsan replied, “I have reached the state of peaceful rest through the grace of Master Pai Chang. Now I have come back home to pay my debt of gratitude to you.”
The old teacher then prepared a great festival in his young disciple’s honor, summoned the monks in the monastery to the assembly hall, and besought Shen Tsan to preach the dharma to all. Whereupon Shen Tsan ascended to the high seat and, following the tradition of Pai Chang, preached as follows:

“Singularly radiating is the wondrous light
Free from the bondage of matter and senses.
Not binding by words and letters,
The essence is nakedly exposed in its pure eternity.
Never defiled is the mind-nature;
It exists in perfection from the very beginning.
By merely casting away your delusions
The suchness of buddhahood is realized.”

As soon as the old teacher heard this stanza, he was immediately awakened.

A man phones up the mental hospital and asks, “Can you tell me who is in room number 12, please?”

“There is nobody in that room, sir,” comes the reply.

“Ah good, that means I have escaped!”

Man is absolutely unaware of his own being. He knows everything else, he tries to know everything else – except his own self, for the simple reason that he takes himself for granted. He thinks as if he knows himself And there is the fundamental error, the most fundamental mistake one can commit.