1. An expression of respect in ancient times
For example, wearing shoes in court was not allowed, and sacrifices were not allowed. Regarding this, there are the words of Cao Cao himself as evidence. Cao Cao said: "When you go to the ancestral temple and go to the hall, you should untie me. I was ordered to go to the temple with swords. Now there is something going on in the temple, so I will untie you." What does it mean? It is a rule that I, Cao, have to take off my shoes when making sacrifices and going to court. I, Cao, have obeyed the imperial edict and can wear shoes when going to court, but the edict does not allow me to wear shoes when performing sacrifices. So during the sacrificial ceremony, like all of you, I wear bare shoes. Put your feet on.
2. The etiquette of going barefoot in formal occasions
Only found in "Zuo Zhuan" and "Song Shu". From the Western Han Dynasty to the Sui and Tang Dynasties, the ancients mainly went to court, offered sacrifices and attended banquets. "Take off your shoes", there are no strict requirements as to whether the small shoes and socks underneath also need to be taken off.
3. After the Sui and Tang Dynasties
The sitting posture of Chinese people changed completely. Taking off shoes was no longer necessary in terms of hygiene, and the etiquette of taking off shoes when sitting down gradually disappeared. Probably starting from the Song Dynasty, there has been another U-turn. Except in the religious circles, the more clothes you wear, the more respectful you are. When officials go to court, they not only have to wear shoes, but also put on a layer of boots outside the shoes.