This sentence comes from chapter 16 of The Analects of Confucius Jishi, and the original text is:
Confucius said: "A gentleman has three precepts: when he is young, his blood gas is uncertain, so he should be cautious; It is also strong and bloody, and it is fighting; I am also old, my blood gas is declining, and I have to quit. "
It means: Confucius said: "A gentleman takes three as a precept. When he was young, his blood was still immature and he should get rid of his infatuation with women. " When you are mature and full of blood, you must give up fighting with others; When you are old, your blood is already weak, so you should abstain from greed. "
Extended data:
This is Confucius' advice on the problems that people need to pay attention to from adolescence to old age. This is still necessary for people today.
The Three Commandments of The Analects of Confucius is selected from the sixteenth chapter of The Analects of Confucius.
The Analects of Confucius is one of the classic works of Confucian school, which was compiled by Confucius' disciples and their descendants. It mainly records the words and deeds of Confucius and his disciples, and embodies Confucius' political opinions, logical thoughts, moral concepts and educational principles. It is also called "Four Books and Five Classics" with Daxue, The Doctrine of the Mean, Mencius, The Book of Songs, Shangshu, Book of Rites, Yijing and Chunqiu. There are twenty popular Analects of Confucius.
References:
Baidu encyclopedia-three precepts of the Analects of Confucius