It is one of the four great uncial codices and contains the oldest complete copy of the New Testament. Discovered by Constantin von Tischendorf in 1844, it remains one of the most important Greek texts for biblical scholarship.

Codex Alexandrinus is one of the four Great uncial codices and among the earliest and most complete manuscripts of the Bible. It is the oldest manuscript to use larger letters to indicate new sections, and it was the first manuscript of great importance and antiquity to be extensively used by textual critics.