Many of the classical Greek genres, such as drama and choral lyric poetry, had been obsolete by late antiquity, and all medieval literature in the Greek language was written in an archaizing style, which imitated the writers of ancient Greece. This practice was perpetuated by a long-established system of Greek education where rhetoric was a leading subject. A typical product of this Byzantine education was the Greek Church Fathers, who shared the literary values of their pagan contemporaries. Consequently, the vast Christian literature of the 3rd to 6th centuries established a synthesis of Hellenic and Christian thought. As a result, Byzantine literature was largely written in a style of Atticistic Greek, far removed from the popular Medieval Greek that was spoken by all classes of Byzantine society in their everyday lives. In addition, this literary style was also removed from the Koine Greek language of the New Testament, reaching back to Homer and the writers of ancient Athens.
In this manner, the culture of the Byzantine Empire was marked for over 1000 years by a diglossy between two different forms of the same language, which were used for different purposes. However, the relations between the "high" and "low" forms of Greek changed over the centuries. The prestige of the Attic literature remained undiminished until the 7th century AD, but in the following two centuries when the existence of the Byzantine Empire was threatened, city life and education declined, and along with them the use of the classicizing language and style. The political recovery of the 9th century instigated a literary revival, in which a conscious attempt was made to recreate the Hellenic-Christian literary culture of late antiquity. Simple or popular Greek was avoided in literary use and many of the early saints' lives were rewritten in an archaizing style. By the 12th century the cultural confidence of the Byzantine Greeks led them to develop new literary genres, such as romantic fiction, in which adventure and love are the main elements. Satire made occasional use of elements from spoken Greek. The period from the Fourth Crusade to the Fall of Constantinople saw a vigorous revival of imitative classicizing literature, as the Greeks sought to assert their cultural superiority over the militarily more powerful West. At the same time there was the beginning of a flourishing literature in an approximation to the vernacular Modern Greek. However the vernacular literature was limited to poetic romances and popular devotional writing. All serious literature continued to make use of the archaizing language of learned Greek tradition.
Byzantine literature has two sources: Classical Greek and Orthodox Christian tradition. Each of those sources provided a series of models and references for the Byzantine writer and his readers. In occasion, both sources were referred to side by side, for example when emperor Alexius Comnenus justified his actions of seizing church property to pay his soldiers by referring to the earlier examples of Pericles and the biblical king David.
The oldest of these three civilizations is the Greek, centered not in Athens but in Alexandria and Hellenistic civilization. Alexandria through this period is the center of both Atticizing scholarship and of Graeco-Judaic social life, looking towards Athens as well as towards Jerusalem. This intellectual dualism between the culture of scholars and that of the people permeates the Byzantine period. Even Hellenistic literature exhibits two distinct tendencies, one rationalistic and scholarly, the other romantic and popular: the former originated in the schools of the Alexandrian sophists and culminated in the rhetorical romance, the latter rooted in the idyllic tendency of Theocritus and culminated in the idyllic novel. Both tendencies persisted in Byzantium, but the first, as the one officially recognized, retained predominance and was not driven from the field until the fall of the empire. The reactionary linguistic movement known as Atticism supported and enforced this scholarly tendency. Atticism prevailed from the 2nd century BC onward, controlling all subsequent Greek culture, so that the living form of the Greek language was obscured and only occasionally found expression in private documents and popular literature.
Alexandria, the intellectual center, is balanced by Rome, the center of government. It is as a Roman Empire that the Byzantine state first entered history; its citizens were known as Romans (Rhomaioi), its capital as New Rome (Constantinople). Its laws were Roman; so were its government, its army, and its official class, and at first also its language and its private and public life. The organization of the state was very similar to that of the Roman imperial period, including its hierarchy and bureaucratic elite.
It was in Alexandria that Graeco-Oriental Christianity had its birth. There the Septuagint translation had been made; there that that fusion of Greek philosophy and Jewish religion took place which culminated in Philo; there flourished the mystic speculative Neoplatonism associated with Plotinus and Porphyry. At Alexandria the great Greek ecclesiastical writers worked alongside pagan rhetoricians and philosophers; several were born here, e.g. Origen, Athanasius, and his opponent Arius, also Cyril and Synesius. On Egyptian soil monasticism began and thrived. After Alexandria, Antioch held great prestige, where a school of Christian commentators flourished under St. John Chrysostom and where later arose the Christian universal chronicles. In surrounding Syria, we find the germs of Greek ecclesiastical poetry, while from neighboring Palestine came St. John of Damascus, one of the Greek Fathers.
Greek Christianity had of necessity a pronounced Oriental character; Ptolemaic Egypt and Seleucid Syria are the real birthplaces of the Graeco-Oriental church and Byzantine civilization in general. Egypt and Syria, with Asia Minor, became for the autochthonous Greek civilization a place where hundreds of flourishing cities sprang into existence, where energies confined or crippled in the impoverished homeland found release; not only did these cities surpass in material wealth the mother country, but soon also cultivated the highest goods of the intellect (Krumbacher). Under such circumstances it is not strange that about nine-tenths of all the Byzantine authors of the first eight centuries were natives of Egypt, Syria, Palestine, and Asia Minor.