The content of the customs clearance document roughly means: Tang Xuanzang is my royal brother in the Tang Dynasty. When he met the emperor of the Tang Dynasty, the emperor personally sent him to the Western Heaven to learn Buddhist scriptures, and Xiao Wang, who passed by, treated him with courtesy. That's roughly what it means. In fact, a few simple words directly indicated three meanings, which made Tang Priest go all the way unimpeded and finally reached the Western Heaven to learn from the scriptures.
First, Tang Xuanzang was the imperial brother of the Tang emperor.
The identity of the royal brothers in the Tang Dynasty is incredible, not only in their own country, but also in the outside world. Therefore, foreign countries dare not be rude to Tang Priest, so they can only meet all his requirements honestly and then stamp the customs clearance documents.
Second, such as the son of heaven in person.
There is such a passage in the original text, that is to say, Tang Xuanzang is not only the emperor's brother in the Tang Dynasty, but also the son of heaven. At that time, the political structure of the Tang Dynasty was very stable, so all the emperors were unexpectedly expanding their careers. Coupled with the prosperous reputation of the Tang Dynasty, many vassal States yearned for the Tang Dynasty, hoping to seek its protection, pay taxes for it and gain bargaining chips with the Tang Dynasty. You know, being able to associate with the Tang Dynasty at that time was a capital worth showing off. The strength of a big country has this advantage. Even if it is sent out, don't worry about her danger, and you can get courtesy wherever you go. So the prestige of the Tang Dynasty was very loud at that time. If the son of heaven comes in person, it will completely shock the monarch of the vassal state. In order to express their friendship with the Emperor of the Tang Dynasty, they treated Tang Xuanzang with great courtesy and respect.
Third, learn from the west.
At that time, Buddhism was very popular in the Tang Dynasty, and the emperor of the Tang Dynasty had such a demand. The vassal States naturally followed suit, and Buddhism was the mainstream religion in many places. As a holy monk in the Tang Dynasty, Tang Xuanzang's position naturally made others dare not neglect.