Christian apologists point out that the New Testament is the best attested document of the ancient world, due to the high and early number of copies. This makes Jesus life, death, and resurrection the best attested story in ancient history.
So, what conclusions shall we draw from the best attested story in ancient history? Well, it's usually important that the scope of one's conclusions match the scope of the evidence. This is a fundamental concept in statistics, where confidence intervals weaken as sample sizes shrink. For example, you cannot survey 25 Italians about their diets, and draw conclusions about the dietary habits of the human species. Another example, you cannot analyze a reported UFO sighting and draw conclusions about the nature of life on other planets. The grandiose scope of such conclusions does not match the very limited scope of the evidence.
The conclusion that "Jesus is God" is a conclusion of tremendous scope. Actually, it is the largest scope of any claim that could be made. It is a theory of all things, of the origins, purpose, and future of the universe and the human race, and of the existence and nature of other dimensions/beings and their relationship to us.
So then, what is the scope of the evidence for this gargantuan claim? The answer is: a small collection of ancient Jewish cult writings known as the New Testament. Yes, the only evidence to support the truthfulness of New Testament stories are the New Testament stories themselves. The stories introduce the main character Jesus, posit the gargantuan claim that he is God, and sadly serve as the only evidence for that claim.
But what about the fact that it's the "best attested document in ancient history"? Doesn't that give it a leg up? Well, once again, where does all this attestation for the New Testament come from? The New Testament!!! By "attestation", apologists are merely referring to the fact that the stories have been copied a lot, as there are a few copies of the same stories (often nearly word-for-word) within the New Testament, and the New Testament has been copied quite a bit throughout time. There is no outside attestation of the actual events. Quite the opposite, the rest of the world regarded this cult's beliefs as baloney, much as we regard cults today. It's all-too familiar, a small cult reports a universe-rattling event which oddly seems to have gone unnoticed by the rest of the population. No matter how you attempt to reconstruct the events of Jesus' life and death, you are reconstructing events which, at the time, failed to convince the vast majority of people that Jesus was God. I want to restate this important point; the Christian apologist is attempting to convince us of events which did not convince the vast majority of people who were actually there during the events (that's why Judaism still exists). To call the events "attested" is like putting a single drop of lemon juice into a pitcher of grape juice and calling it lemonade.
If the actual events didn't even convince those who were there, why should the sparse stories convince us 2000 years later?
So then, what conclusion shall we draw from a collection of ancient writings which depict twelve men following around a man they believed to be God? The answer is quite simple; we should conclude there existed a small ancient cult who believed their leader was God. To then adopt the cult's beliefs would require ignoring the tremendous deficit between the scope of the conclusion and the scope of the evidence, a mistake that many religions have made. (any mormons reading this?)
When it comes to drawing conclusions of such universal scope, we should require evidence that is similar in scope, not a handful of ancient cult stories. Analyzing the New Testament stories and concluding that Jesus is God (and all the theology/religion that comes with it), is an even greater stretch than analyzing a UFO sighting from 5 country-bumpkins and subsequently devoting the rest of your life to educating others about alien biology, and personally preparing for another extraterrestrial visit. Don't be a slave to stories.
