There is a story about "Xin Zhai" recorded in "Zhuangzi" (also known as "The Nanhua Zhen Jing"). Yan Yuan asked Confucius for advice. Confucius said, "Fast, and then I will tell you." Yan Yuan said, "I am poor. I have not drunk wine or eaten meat for a long time." Confucius said, "This is the fast for sacrifice, not 'Xin Zhai'. Concentrate your mind. Do not listen with your ears, but with your heart. Do not listen with your heart, but with your qi (vital energy). Purify your heart to get rid of desires. Cleanse your spirit to remove impurities and burdens. Suppress your wisdom to eliminate thoughts. Without thoughts and worries, you can focus on the Tao. Without desires, you can take delight in the Tao. Without impurities and burdens, you can be in harmony with the Tao. Since there is no other thought in the heart, it is called concentration of the mind."

As it is said in "Zhuangzi": "The Tao should not be mixed. If it is mixed, there will be multiplicity. If there is multiplicity, there will be disturbance. If there is disturbance, there will be worry. If there is worry, it cannot be remedied." Therefore, "Xin Zhai" means to eliminate distracting thoughts, make the state of mind empty, quiet and pure, and understand the Great Tao.