Who knows the origin of sweeping graves in winter solstice?

Sacrificing one's ancestors in front of a grave is called grave sweeping or worship. This custom originated in China a long time ago. As early as the Western Zhou Dynasty, people attached great importance to tombs. In Mencius' article about Qi people in the Eastern Zhou Dynasty and the Warring States Period, he also mentioned a ridiculed Qi person who often went to the tombs of Dongguo to beg for food and worship tombs. It can be seen that the wind of sweeping graves was very popular in the Warring States Period. When I arrived in Xuanzong of the Tang Dynasty, I decided to sweep the grave with cold food as one of the "five rites" at that time. Therefore, whenever Tomb-Sweeping Day comes, "the fields and roads are crowded with scholars and women, and all servants and beggars must go to their parents' graves. (Liu Zongyuan's Book with Xu Jingzhao) Grave sweeping has become an important social custom. (Originally, the Cold Food Festival and Tomb-Sweeping Day were two different festivals. In the Tang Dynasty, the day of grave sweeping was designated as Cold Food Festival. The correct date of the Cold Food Festival is from winter to the future 105, which is around Qingming, so Qingming and Cold Food Festival meet together)

In the Tang and Song Dynasties, the solstice in winter was a day to worship gods and ancestors. On this day, the emperor went to the suburbs to hold a ceremony to worship the gods. On this day, people must worship their parents and elders. Except for families offering sacrifices to their immediate ancestors, all those who have "ancestral halls" or "ancestral halls" should hold ceremonies offering sacrifices to gods, which are called "winter sacrifices". Some of them are held ten days before the winter solstice, and the ceremony is very grand. After the festival, banquets are held to entertain relatives and friends, which has a profound effect on caring for relatives and neighbors.

At present, there are still some places that celebrate festivals from winter solstice to Sunday, and gradually expand to sweep graves.