The facts presented in the New Testament have a large amount of corroboration from sources outside the Bible (see here, and here, and here). The typical objections to these facts is claiming the Bible to be historical fiction and dismissing miracles outright. To see the fallacy of these typical objections, see here and here.
Let us turn to how the style of writing is evaluated……not by laymen, but by literary scholars. I know of two who were atheists who were teaching literature at the university level, then became Christian when they turned their eye toward the Bible.
Dr. C. S. Lewis was a professor of literature at Oxford and Cambridge. He said the following:
All I am in private life is a literary critic and historian, that’s my job. And I am prepared to say on that basis if anyone thinks the Gospels are either legend or novels, then that person is simply showing his incompetence as a literary critic. I’ve read a great many novels and I know a fair amount about the legends that grew up among early people, and I know perfectly well the Gospels are not that kind of stuff. (Christian Reflections, 209)
Dr. Holly Ordway was also an atheist with a PhD in literature, teaching at the university level, who then became a Christian partly by reading Christian literary works:
I read through the Gospel narratives again, trying to take in what they said. I had to admit that–even apart from everything else I had learned–I recognized that they were fact, not story. I’d been steeped in folklore, fantasy, legend, and myth ever since I was a child, and I had studied these literary genres as an adult; I knew their cadences, their flavor, their rhythm. None of these stylistic fingerprints appeared in the New Testament books that I was reading. In Paul’s letters, I heard the strong, clear voice of a distinctive personality speaking of what he knew to be true. The Gospels had the ineffable texture of history, with all the odd clarity of detail that comes when the author is recounting something so huge that even as he tells it, he doesn’t see all the implications. (Not God’s Type, 117)
So when we examine the historical narratives of the New Testament, we have not only external, factual corroboration of the minute details, we also have testimony of expert witnesses that tell us the accounts do not exhibit the style of fictional writing. As with anything historical, we cannot prove the New Testament narratives the same way we solve a math problem. Instead we look at the evidence and determine what is reasonable. The New Testament accounts show all the signs of being exactly what they claim: eyewitness accounts of actual historical events.
Lewis and Ordway demonstrate that when educated people look at the evidence with reason in mind, the conclusion is in favor of the truth of the scriptures. We would all do well to read the Bible with these facts in mind.