In ancient China, people had strict requirements on etiquette. Threshold is the boundary between inside and outside, which is a part of China's concept of hierarchical etiquette. Threshold is the best embodiment of social status and identity. At present, the gates of high-rise buildings, modern residential buildings, government agencies and enterprises are all electric, the threshold is gone, and many barrier-free facilities have been built, which has absorbed western civilization.
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The ancient threshold is a symbol of power and status. The higher the threshold, the more distinguished the host. For example, the threshold of the Forbidden City is very high. If you don't lift your feet, it's not easy to cross.
Royal design is meaningful. When civil and military officials go to the temple, everyone has to step in and cross the threshold, so they need to bend over. After crossing the threshold, it is even more important to keep a bent posture, indicating that you dare not look at the dragon's face. This is awe and respect for the emperor. And the threshold of the royal family is not how you want to cross it, let alone who wants to cross it.
Ordinary officials cannot cross the threshold from the middle. Civil servants should come in from the right and military attache from the left. Officials below grade seven can only look back on them, because they are not even qualified to enter the threshold.
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