Codex Sinaiticus and Codex Vaticanus, two of the great uncial codices, representatives of the Alexandrian text-type, are considered excellent manuscript witnesses of the text of the New Testament. Most critical editions of the Greek New Testament give precedence to these two chief uncial manuscripts, and the majority of translations are based on their text.
Friedrich Constantin von Tischendorf [1815-1874] Tischendorf was a world-leading biblical scholar who rejected higher criticism, which led to his noteworthy success in defending the authenticity of the Bible text.
Codex Sinaiticus (01, א) alone has a complete text of the New Testament. It is dated to c. 330–360 C.E. The codex is an Alexandrian text-type manuscript written in uncial letters on parchment in the 4th century. Scholarship considers the Codex Sinaiticus to be one of the best Greek texts of the New Testament, along with the Codex Vaticanus.