六祖大師法寶壇經 1.105

1.105

The monk Zhichang was a native of Guixi in Xinzhou. Having left the household in his youth, his aspiration was to seek seeing into his nature. One day he came to pay homage. The Master asked him, "Where have you come from? What matter do you seek?"
He said, "I recently went to Mount Baifeng in Hongzhou to pay homage to the Upādhyāya Datong, and received his instruction on the meaning of seeing into one's nature and attaining buddhahood. Not having resolved my doubts, I came from afar to pay homage and submit myself, humbly hoping the Upādhyāya will compassionately give me instruction."
The Master said, "What words did he speak? Try citing them so I may see."
He said, "When I arrived there, altogether three months passed without my receiving any instruction. Because of my urgency for the Dharma, one evening I went alone into his room and asked, 'What is my fundamental mind and fundamental nature?' Datong then said, 'Do you see empty space?' I replied, 'I see it.' He said, 'Do you see empty space having any appearance?' I replied, 'Empty space has no form; what appearance could it have?' He said, 'Your fundamental nature is just like empty space. Utterly without a single thing that can be seen is called right seeing; without a single thing that can be known is called true knowing. There is no blue or yellow, long or short; merely seeing that the original source is pure and the body of awakening is completely bright is called seeing into one's nature and attaining buddhahood, and is also called the vision and knowledge of the Tathāgata.' Although I heard this explanation, I have still not resolved it clearly, and beg the Upādhyāya to give me instruction."
The Master said, "What that master said still retains seeing and knowing, and therefore caused you not to understand clearly. I now present you with a verse: