Greek has been handed down.
First of all, in the Eastern Roman Empire, ancient Greek is not only the common working language of the upper class with Latin, but also used more in the ordinary class. The main reason for this situation is that before being conquered by Rome, almost all the areas of the Eastern Roman Empire were controlled by the successors of the Alexander Empire. The countries in the Near East have long regarded ancient Greek as the main common language.
For example, according to the statistics of later generations, most of the manuscripts circulated in the Eastern Roman Empire in Justinian era were written in ancient Greek except for laws, and only a few writers used Latin or Syrian as their creative language.
Of course, the widespread use of ancient Greek does not mean that there is only one Greek. On the contrary, in the Eastern Roman Empire at that time, there were at least three Greek "schemes" besides Attica Greek in Athens and Alexandria Greek in Egypt handed down from the Roman Republic. First of all, classical Greek, which is well known to upper-class cultural talents, has a classical phonetic symbol, which is similar to hieroglyphics that were still widely used in Egyptian religious forces at that time, and has almost become a "language of death". Secondly, the written Greek language used by scholars, especially in the professional field. At that time, in the religious, grammar, medical and other professional fields of the Eastern Roman Empire, the usage rate of written Greek was much higher than that of Latin, and many professionals also used Greek vocabulary when writing Latin. In fact, until today, nearly half of proper nouns in English medical vocabulary still come from Greek. Finally, similar to Latin popular in western Rome, in the fields of commerce and shipping, the Eastern Roman Empire also produced the so-called "Romanesque Greek". This Greek gradually evolved from the long-term communication between Romans and Greek businessmen. Its greatest feature is the extensive use of Romanesque grammar and the integration of dialect words from all over the Mediterranean.
But in any case, compared with the Western Roman Empire, all social classes use Latin, and almost everyone in the Eastern Roman Empire uses Greek from temples to streets. This situation is not intentional by the ruling class of the Eastern Roman Empire, but stems from the policy of accommodating losers and opening up culture gradually formed by Rome in the course of hundreds of years of development.
Latin is used in law and religion.
Since Greek has an absolute advantage in the Eastern Roman Empire, the Eastern Roman Empire must give Greek an appropriate status. This position is higher than Greek and Latin in the late Roman Republic and the Roman Empire. Moreover, this kind of catering to the use of folk language is combined with the struggle between the eastern and western churches, the political struggle between the eastern and western Roman empires, and especially the legislative struggle. For example, Justinian's code, legal compilation and legal ladder are all written in Latin, and the official report of the same period is also written in Latin. However, because Justinian decided that the ruling center was in the Eastern Roman Empire, he finally decided to write the law in ancient Greek for the first time in the new law. Since then, in the legal field that was originally dominated by Latin, the Eastern Roman Empire also used ancient Greek as its official working language.
As far as the language of the Christian church is concerned, the situation is more complicated. First of all, from the Old Testament, Greek classics appeared earlier than Latin classics. Because before Christianity was declared as the official religion of Rome, it was always circulated among the people in an underground way, and the language of preaching and writing must be a common language that ordinary people can understand. Therefore, the churches in the Eastern Roman Empire have always used Greek as their working language, while Latin, which people are most familiar with, is used in the Western Roman region. Therefore, the religious documents in Justinian era that we can see now, as long as they are theological papers, are almost all written in Greek of the Eastern Roman Empire. However, all the documents of reconciliation negotiations with the Western churches represented by Rome were written in Latin of the Western Roman Empire. Religious differences, common language differences and political factors eventually led to the long-term division of the eastern and western churches. The use of Latin or Greek has also become the most important feature that distinguishes Orthodox Christianity from Catholicism.
So, is it possible for Rome to achieve language unification? Considering that Rome, the country and the empire adopted the policy of tolerating losers and opening up culture in the early stage, it is unlikely that Roman officials will make great efforts to suppress the circulation and use of Greek. Moreover, the dual-track system of Greek and Latin also gave the Roman elite a sense of cultural superiority.
A lifeless language
By the time Christianity became the official religion of Rome, the church might have come out to unify the religious language, and then unified the language for the empire by spreading the power of religion. Unfortunately, at this time, the ruling system of the Roman Empire gradually collapsed. After the collapse of the Western Roman Empire, the eastern and western churches consciously increased the differences between Latin and Greek in the eastern and western empires because of the struggle for power and interests. As a result, although Latin and Greek have become the unique common languages of their respective countries, they cannot cross each other's regions. Therefore, the collapse of the Roman Empire and the division of the church completely destroyed the possibility of the unification of the Roman language and writing.
Interestingly, with the help of medieval religions, Latin once again gained the status of a common language in Europe. However, with the Renaissance and the emergence of the nation-state system, all ethnic groups began to promote their own spoken and written languages in all aspects, including religion. As a result, Latin can only gradually withdraw from daily circulation and become a religion and a special written language similar to early Egyptian hieroglyphics. Although a large number of Latin elements have been used in the languages of the Roman family and the international alphabet system in modern times, the language itself has lost its vitality and it is difficult to become a common working language.