There is often much scepticism by agnostics and atheists alike in terms of the authenticity of the New Testament. Largely because complete versions are not existent from before the 4th Century. There are fragments that exist from the 2nd century just decades after the originals were written.
One of the main reasons for this is that the Bible itself was not officially decided until the 4th century. Until then the early Church and its churches based their teachings on the teachings of the Apostles and their disciples. The letters of the Apostles, the witness accounts and the records of them were in circulation but they had not yet decided on a universal document. It became important to record these documents.
What is undeniable is that the Early Church stood for the central message to Christianity -Jesus Christ’s message to the world in his death and resurrection. Established by the Apostles who new Christ themselves – there are many which stand still today.
These institutions existed before the completed Gospel. They developed and discipled the Early Church fathers, many who directly succeeded the Apostles themselves. Characters such Polycarp, Ignatius and Clement of Rome or Iranaeus to name a few, many of whom real copies of their writings exist today.
In fact we should praise God for the overwhelming and awesome existence of such an evident and authentic Gospel. A historic New Testament is comparably strong to any other documents of the time. The fact of the evidence for the lives of God’s apostles, the churches they established, their recorded ordinances and martyrdoms stand to show why Christianity has stood and what for.
Questions over the ages of complete documents isn’t going to defeat the truth of the message that the Church has, in all essence stood for since the time of Christ. Indeed the culture of Judaism from before then also stands to reason.