Explanation: generally speaking, it refers to what you have experienced, and you know the joys and sorrows.
Source: Songshi Daoyuan "Jingde Dengchuan Record": "Although a certain armor follows Huang Meizhong, he does not save his face. Now instruct me to enter the place, just like drinking water, knowing it well. Walker is also a teacher. "
York & gt in the Southern Song Dynasty "drinks water like fish, and you know it when you are warm and cold."
The original definition refers to cold and warm water, and the drinker knows it. Zen is used to describe the realm of self-enlightenment. It is also a metaphor for the depth of learning experience, only oneself know.
From Don Subakala Sinha's "The Great Sun Sutra" Volume 12: "If you drink water, you will know whether it is warm or cold."
Examples are now raised to places, such as drinking water. Today's walker is someone's teacher. (Songshi Daoyuan's Record of Jingdezhen and Dengchuan, Volume 4)