The full text means: "There is a saying that as a teacher, he is proud of having noble moral character, and a person with bad moral character can't be a teacher of others." And the "Tao" in this sentence refers to a sentence, a thing or something. This sentence is mainly about morality. We like watching martial arts movies. The tallest person in it must have martial arts and dignity. The other school has high martial arts, but no virtue, and is a villain. Generally speaking, a man without virtue gives him a team, and he can lead the team beyond redemption. Give him a country, and he will bring disaster to the country and people. In the work, we should use people only for virtue, cultivate virtue without talent, use it carefully and resolutely not use it.