Zheng Zhuanggong made a poisonous oath that he would only meet his mother in the underworld. Zheng Zhuanggong's mother was very partial because he was born with his feet first, which frightened his mother. Therefore, his mother disliked her very much and did not like him at all. She only liked his younger brother, and he Her mother also advised her husband many times to give up the throne of emperor to her youngest son, but her husband always disagreed.
His mother almost killed Zheng Zhuanggong, so Zheng Zhuanggong was very angry and swore such a poisonous oath. Her mother was very partial to her younger brother, and after he became the emperor, her mother was still very partial to her younger brother. However, his younger brother was very ambitious and wanted to be the emperor, but he was not satisfied at the time. As for the land his brother gave him, he has been occupying the surrounding land. Later, his land became very large, and his soldiers and horses were also very sufficient, so he was ready to launch a mutiny, so he let his His mother served as an internal agent for him in his brother's city. When he attacked his brother's city, he asked his mother to open the city gate and let his army in. However, Zheng Zhuanggong knew about this plan in advance and he felt that His mother was so cruel that she wanted to kill herself for her brother, so he was very angry and swore such a poisonous oath.
But a year later, he regretted that he had sworn such a poisonous oath. A minister told him that you can dig a hole in the ground until you find water, so that you can have sex with you. The mother met here. At that time, he saw that others could honor their parents, and he was very envious. At this time, he thought of his mother, so he told one of his ministers about it, and then his minister gave him a plan to let him He ordered people to dig a hole underneath. When the spring was dug out, the hole would be completed, and he and his mother could meet under the hole. In this way, no one would say that Duke Zhuang of Zheng broke his promise.
In fact, Zheng Zhuanggong swore this poisonous oath at that time because he was very angry. He regretted it not long after, but later a minister helped him solve this trouble.