"A gentleman talks but doesn't do it." It comes from the Analects of Confucius. Confucius said, "A gentleman should try his best to speak cautiously and act quickly."
"The ancients couldn't say that they were ashamed of it." ("Li Ren")
"A gentleman is ashamed of his words, but he does not stop." ("Xianwen")
"If you don't say it, it's hard to do it." "("Xian Wen ")
Zi Gong asked the gentleman. Confucius said, "Speak before you act." (Politics)
Confucius said, "A gentleman does not think about satiety and security. He is sensitive to things, but he is very cautious about what he says. " ("learning")