No, it was written down, treasured, reproduced, and distributed church by church all around the mediterranean and used by people who knew the authors and each other. So from the very beginning these eyewitness accounts were shared with other eyewitnesses. Today we have 5600 fragments dating back to a generation that knew the authors. This is how we know we have correct information: massive redundancy. During the first few hundred years you would be killed if caught with one of these documents so there is only one reason to keep, reproduce, and share them. They believed those eyewitnesses.