In ancient times, a government courier in China went out early in the morning one day. Out in the wilderness, a man carrying valuables saw the courier holding a long spear and got scared, so he hid in the bushes.
The courier heard noise coming from the bushes but couldn't see anybody. He thought a tiger or a cougar was hiding in the bushes, so he used his spear to stab into the bushes and killed the man accidentally. After the courier realized that he had killed someone by mistake, he didn't report it to the government. Instead, he took the person's valuables, left the body in the bushes, and walked away.
No one had seen the incident. The courier became very rich and got married. His wife gave birth to a daughter.
One day when he was standing outside his house, he saw the man whom he had killed by mistake. He ran into the house, shut the door, and peeked out from behind the door. The man walked into the home of his neighbor who was a tanner.
Soon after, the wife of the tanner gave birth to a son. The courier, remembering what he had done, was very nice to the neighbor and his son. When the courier’s daughter grew up, he prepared to marry his daughter to the tanner’s son. The tanner was so pleased that he made his son promise to treat the courier as his own father.
One hot summer day, the courier got very drunk, went to bed, and started to sweat profusely. The tanner's son, who was looking after him, was using a knife to wipe off the sweat. The courier, being drunk, felt something on his stomach, thought it was a mosquito, and slapped it, driving the knife into his stomach.
Before he died, he told his family the entire story and decided to immediately marry his daughter to his neighbor's son, and gave him all his wealth. He then told them that he had come by this unexpected wealth due to greed. “That is why I had this unexpected disaster. Now I have paid him back. From now on, all of you have to be good people and don't do anything against your conscience.”
(From The Way to Gather Good Fortunes and Avoid Disasters)