The Codex Alexandrinus (London, British Library, MS Royal 1. D. V-VIII; Gregory-Aland no. A or 02, Soden δ 4) is a 5th century manuscript of the Greek Bible, containing the majority of the Septuagint and the New Testament. It is one of the four Great uncial codices. Along with the Codex Sinaiticus and the Vaticanus, it is one of the earliest and most complete manuscripts of the Bible. Wettstein designated it in 1751 by letter A, and it was the first manuscript to receive thus a large letter as its designation.
It derives its name from Alexandria where it resided for a number of years before it brought by the Eastern Orthodox Patriarch Cyril Lucaris from Alexandria to Constantinople. Then it was given to Charles I of England in the 17th century. Until the later purchase of the Codex Sinaiticus, it was the best manuscript of the Greek Bible deposited in Britain. Today, it rests along with Codex Sinaiticus in one of the showcases in the Ritblat Gallery of the British Library.
As the text came from several different traditions, different parts of the codex are not of equal textual value. The text has been edited several times since the 18th century.
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