In The Master of Yin and Yang, Abe Harumi's explanation of the spell.

In fact, the duties of Yin and Yang teachers are divination and making calendars.

Divination is to infer the omen of something through some phenomena.

Making a calendar is making a yellow calendar, just like our lunar calendar, which says what day it is, what to do and what not to do.

Therefore, a spell is something used to bind things.

Name is the simplest curse. By name, you can bind people, just as someone calls your name and you will agree. It's the same reason that Zijin Hulu collects the Monkey King. Without fame, people's existence is equivalent to non-existence. In magic, the name also becomes a curse. Through his real name, he can be ordered to do something, just like hypnosis.

Time is an invisible thing. The so-called time is just a combination of the movements of many things. And we bind him to time and divide time into years, months and days, which can be deduced and observed like coordinate axes. This world, this dynasty and this country are meaningful. Our days are also meaningful.

There is a beginning of knot and a beginning of history, so there is China, isn't there?