What does it mean that people who get up and don't eat are afraid of breaking their word?

The reason why Wu Qi doesn't eat and wait for his old friends is that he is afraid that he will not keep his word.

Yesterday, Wu Qi went out to see an old friend (2) and stopped eating. An old friend said, "promise." Wu Qi said, "I'll wait for you to have dinner together." . "Old friends didn't come in the evening, Wu Qi didn't eat, waiting for him. The next morning, I sent someone to find my old friend. The old friend came and only had dinner with him. Wuqi didn't eat, because he was afraid that he would not keep his word while waiting for his old friends. If you believe it, you should be able to serve the three armed forces, right? If you want to serve the three armed forces, you must believe.

(selected from "Longmen Zi Ning Dao Ji")

Once upon a time, Wu Qi met an old friend when he went out, and was left for dinner. The old friend said, "Good." Wu Qi said, "(I am at home) waiting for you to have dinner together." The old friend didn't come in the evening, and Wuqi didn't wait for him to eat. The next morning, (Wuqi) sent someone to find an old friend. When the old friend came, he had dinner with him. The reason why Wu Qi doesn't eat and wait for his old friends is that he is afraid that he will not keep his word. He insisted on his credit to the point where he could convince the army! To convince the army, you must not break your word (as a general).

This shows that "people can't stand without faith" and so on, all of which show the importance of trustworthiness.