Four great uncials

The great uncial codices or four great uncials are the only remaining uncial codices that contain (or originally contained) the entire text of the Greek Bible (Old and New Testament).

Only four great codices have survived to the present day: Codex Sinaiticus, Codex Vaticanus, Codex Alexandrinus, and Codex Ephraemi Rescriptus. Although discovered at different times and places, they share many similarities. They are written in a certain uncial style of calligraphy using only majuscule letters, written in scriptio continua (meaning without regular gaps between words). Though not entirely absent, there are very few divisions between words in these manuscripts. Words do not necessarily end on the same line on which they start. All these manuscripts were made at great expense of material and labour, written on vellum by professional scribes. They seem to have been based on the most accurate texts in their time.

All of the great uncials were written on fine vellum, with the leaves arranged in quarto form. The size of the leaves is much bigger than in papyri codices:

Codex Vaticanus uses the most ancient system of text division in the Gospels. Sinaiticus, Alexandrinus, and Ephraemi have the Ammonian Sections with references to the Eusebian Canons. Codex Alexandrinus and Ephraemi Rescriptus use also a division according to the larger sections – κεφάλαια (chapters). Alexandrinus is the earliest manuscript which uses κεφάλαια. Vaticanus has a more archaic style of writing than the other manuscripts. There is no ornamentation or any larger initial letters in Vaticanus and Sinaiticus, but there is in Alexandrinus. Vaticanus has no introduction to the Book of Psalms, which became a standard after 325 AD, whereas Sinaiticus and Alexandrinus do. They have different order of books.

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