What is the origin of eating jiaozi on the winter solstice?

Jiaozi's original name was Joule, which was invented by Zhang Zhongjing to treat the poor people who were hungry and cold, and their ears were frozen. The day when Zhang Zhongjing started to open a shop to save people happened to be the solstice in winter, so many people ate jiaozi to commemorate him on the solstice in winter, and it became a custom like the Dragon Boat Festival over time.

When you eat jiaozi on the solstice in winter, you will never forget the kindness of Zhang Zhongjing, a "medical sage", in "Quhan Joule Decoction". Up to now, there is still a folk song in Nanyang, which is called "jiaozi Bowl, and nobody cares about frozen ears." .

The Winter Solstice Festival originated in the Han Dynasty, flourished in the Tang and Song Dynasties, and has been passed down to this day. Lu even said that the winter solstice is as big as a year. This shows that the ancients attached great importance to the winter solstice. People think that the winter solstice is a natural transformation of yin and yang and a blessing from heaven. In the Han Dynasty, the winter solstice was the "Winter Festival", and the government held a congratulatory ceremony called "He Dong", which was a routine festival.