It is sometimes suggested that the New Testament as we know it did not exist until centuries after Jesus, and that the books comprising the New Testament were not considered divine or authoritative until much later than the first century.
One problem with the theory that the books in our New Testament were not considered Scripture in the first century is that the authors of the New Testament books specifically refer to the other author's books as being Scripture! Take a look at 2 Peter 3:15-16:
Bear in mind that our Lord's patience means salvation, just as our dear brother Paul also wrote you with the wisdom that God gave him. He writes the same way in all his letters, speaking in them of these matters. His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction.
Here Peter refers to the wisdom found in Paul's letters. Note Peter's wording: He says Paul's letters contain things that are hard to understand just like the other Scriptures. Peter considered at least some of Paul's letters to be Scripture, equal in authority to the Old Testament.
I came across another passage this week that seems to treat other New Testament books as Scripture, 1 Timothy 5:18:
For the Scripture says, "Do not muzzle the ox while it is treading out the grain," and "The worker deserves his wages."
The first quote is from Deuteronomy 25:4. The second is not found in the Old Testament, but it is found in the New Testament. Albert Barnes notes in his commentary that "This expression is found substantially in Matt 10:10, and Luke 10:7. It does not occur in so many words in the Old Testament, and yet the apostle adduces it evidently as a quotation from the Scriptures, and as authority in the case. It would seem probable, therefore, that he had seen the Gospel by Matthew or by Luke, and that he quoted this as a part of Scripture, and regarded the Book from which he made the quotation as of the same authority as the Old Testament. If so, then this may be regarded as an attestation of the apostle to the inspiration of the “Gospel” in which it was found." (Albert Barnes' Notes on the Bible, via e-sword)
Kinda throws cold water on the whole "Constantine put together his own collection of scriptures" myth eh? (Sorry couldn't help referencing The Da Vinci Code again!)
There's an interesting book that I haven't been able to finish reading yet called The First Edition of the New Testament by Dr David Trobisch, which posits the theory that the New Testament we know today was first compiled (in a form identical to or very similar to its present form) in the early 2nd century, not in the 4th century as it is often assumed. It's an interesting but somewhat difficult read, probably in part because it's been translated from its original German form. It's also expensive ($45) considering it's only 184 pages. I'll finish reading it next semester when I'm back at the school library. ðŸ˜‰