"There is no need to harm people, and there is no need to prevent people." This is a folk saying. It means roughly: you can't have bad thoughts of hurting others, but you should also be on guard against others and be alert to others.

Source, Hong Yingming's "Caigen Tan": "The heart of harming people is indispensable, and the heart of preventing people is indispensable; It is better to be bullied than to be bullied. "