One of the things that's coming up quite a bit at the moment in discussions and lectures is the presuppositions that we bring when we come to look at a text.
For example, there are plenty of accounts of Jesus performing miracles.
If someone looks at them with the presupposition that miracles can't happen, they will have to conclude that the account should not be taken at face value, but is either untrue or is using metaphor in some sense to communicate that truth. That's actually an underlying principle behind a lot of modern liberal theology.
They'll look at a passage from the Old Testament, for example, and notice that it has some straightforward historical accounts (which can frequently be verified archaeologically) and a scene where an angel turns up and does something. They'll then conclude that the passage they're reading is actually a composite made by combining a genuine historical document with a fictional account with angels in or something.
On the other hand, a Christian (me, for instance) could read the passage and say “Historical events, yep. Angel appearing, fine. No worries.”
I've got some sympathy with the liberals here. I think they're wrong, and often far too arrogant in stating their position, but I understand where they're coming from.
It looks the same as we might do with the Iliad. The Iliad is a long poem by Homer, about the Greeks attacking and capturing Troy. And again, the Greek gods do a fair bit of stuff. People used to think the account was totally fictional, until some archaeologist with a name like Schliemann or something discovered the ruins of Troy. So what classical historians do now is they try to keep the story, but take all the god-bits out of it. And it's reasonably possible to do – it turns out that the god bits are mostly back story – and you can end up with a story a lot like the one in the film Troy, except with the gay sex bits kept in.
So if that's ok with the Iliad, why isn't it ok with the Bible? The difference is in the role the “supernatural” bits play in the story. In the Iliad, the gods are mostly used to explain motivations (when there could have been other ones), to give ideas to people (which they could have had anyway) and so on. In the Bible, God does much more than that. He doesn't just slightly influence the course of battles, he strikes all of one side dead before the battle starts. He parts rivers to let people through. He brings people who have died in a very real, public and verifiable sense back to life. The Iliad can be rewritten without the god-stuff as the story of a great military victory, which it would make sense to write poems about. Without Jesus' miracles and rising from the dead, there isn't anything special about him for the whole religion to have started around.
So if we look at the Bible with the presupposition that supernatural events don't happen, what we are left with is an impossible puzzle. In the early apostles, we have a group of people who were clearly in a position to know what had happened, claiming not just that there were everyday events to which they attached a supernatural significance, but where the events themselves could only be explained supernaturally and where the events have a significance which is deeply uncomfortable.
It also raises the question as to what the correct presupposition is when we are looking at an alleged supernatural event, and I think I can explain this with reference to science.
Scientists argue about whether cold fusion is possible. Pretty much all serious scientists agree that it hasn't happened, most think that it can't happen either. But that doesn't stop people trying (mostly because it could make whoever discovered it very rich indeed). Suppose that someone claims that they've managed to achieve cold fusion, and that I, as a scientist, am asked to investigate.
What should I assume? Should I go in assuming that cold fusion is impossible, and whatever evidence comes up, keep on believing that it's impossible? No – what would be the point of either asking me to investigate or me investigating? I'd just conclude that it hadn't happened, whether or not I could come up with another explanation.
What I should assume is that it might be possible, and then look at the claims and at alternative explanations.