Do not entertain friends with food.

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).