New Testament Significance
The codex is significant for New Testament study as it gives us some examples of the oldest biblical texts to have survived. For instance, the 4th century Codex Sinaiticus is a prime example of one the best preserved New Testament texts available to us. Scot McKendrick (Head of Western Manuscripts at the British Library) has referred to the Codex Sinaiticus as “one of the world's greatest written treasures," as it is thought to be the oldest and largest bound book to have survived.
Although the codex also holds significance as representing a relatively stable collection of books, in the 4th century there was as yet no fixed order to New Testament scripture. At the time, a number of different manuscripts were circulating. Dale Martin has said that with the invention of the codex there naturally had to be a decision about what went into it and what stayed out (e.g. New Testament History and Literature, Yale University Press). It may be said that the development of the codex greatly aided in the development of the contents and order of the New Testament canon.
Not only was the invention of the codex significant for the New Testament but it was also a watershed moment for the evolution of the book.
The aforementioned Codex Sinaiticus is the oldest surviving complete manuscript of the New Testament, thought to have been written three hundred years after the proposed lifetime of Jesus. This specific codex provides modern scholars with an insight into third and fourth century Christianity. For example, this volume includes books which did not make it into our New Testament canon such as 'The Shepherd of Hermas' and 'The Epistle of Barnabas'. (See also the exhibit for Codex Sinaiticus.)
By having this ancient manuscript we are able to know which books were widely read and circulated by early Christians at the time. Whilst these certain writings were not included in the finalised canon, they still provide utility for exploring the development and density of the Christian tradition as it emerged in the early centuries.