Tao Te Ching

“Zui-Gan called out to himself every day, 'Master.' Then he answered himself, 'Yes, sir.'
And then he added, 'Become sober.' Again he answered, 'Yes, sir.'
After that he continued, 'do not be deceived by others.' 'Yes, sir; yes, sir,' he replied.
”

— Mumon Ekai 無門慧開 1183 – 1260 CE via J. D. Salinger
(Wumen Huikai)
Pioneering pathfinder to the Gateless Gate

from The Gateless Gate, 無門関, 無門關