Chinese Traditional Story: Escape from the Great Plague of the Century

Looking at major plagues throughout history, they all seem to be directly related to the decline of human morality. So, who sets the moral standards for humanity? We know that humans were created by God, and the human world must be managed by God. Throughout history, God has sent some saints, such as Shakyamuni Buddha, Jesus, Lao Tzu, and Confucius, to the world to impart theories and knowledge on how people should live in this world.