As a Christian I knew only One Way - the Bible is the word of God, a unified and consistent work of Lutheran theology. I came to dislike that way, and I still do. I'll happily tolerate your following it, and nod as you tell me how important this belief system is to you, but it's not for me. You see, I can't help following the Christian tenets to their logical conclusion, and that conclusion is evil and inhuman. Luckily Christians don't do this, they color their theology with their own personal characteristics, good or evil depending on the person, but always human: Some bring compassion, others authoritarianism. Some bring their level heads and common sense, others their fanaticism. I brought my skepticism, and there was just no way for me to reconcile that with Christian theology.
How then should an atheist read the Bible? Not as the Devil would, I think. The Devil is a revolutionary free-thinker, a rebel against the injust regime of a cosmic tyrant. The Devil looks for ways to discredit the tyrant, so he searches the Bible for contradictions and faults. But the Christian God does not exist. If he did, I think we humans would need a Devil to stand up for us, but he doesn't, so we don't. The Church does exist, and perhaps in some places it is so powerful that we need human Devils to fight it - atheists like Christopher Hitchens and Richard Dawkins. But here - Norway - is not one of those places. As far as I'm concerned, the war on Heaven is over. The place is still there, in the minds of believers, but I'm fine with that.
Which makes it possible for me to approach the Bible as a truly independent reader. Many can't do this. Christians are the most restricted Bible readers of all - they need to see their theology reflected in every word and paragraph of every book of the Bible. The consequences of finding something that contradicts their theology are so profound and disturbing that they must close their minds to even the possibility. It's all coherent and consistent, otherwise what have I built my life on? There's a neurotic tension here, between the need to respect this ancient collection of books and the need to twist it into something it clearly isn't, that makes it hard for Christians to read the Bible as it really is.
That doesn't mean that what Christian scholars have to say about the Bible is uninteresting. It depends on how heavily their theology chains down the Bible for them. Many Christians are comfortable with reading the Bible as a historical document. By that I mean not claiming that it is historically true, but applying historical methods to it to determine how reliable it is. In Biblical scholarship, there doesn't seem to be a clear line with believers on one side and nonbelievers on the other. There's a mainstream of scholars, believers and nonbelievers, who agree on many important things. For instance, they agree that the Synoptic Gospels - Matthew, Mark and Luke - are more reliable as historical documents than the Apocryphical Gospels, the ones that were left out of the Bible. (Dan Brown-style theories are for cranks.) They agree on the methods to use when analyzing the Bible, how to determine the validity of a source, the strength of a claim. If you want to understand the Bible, you can't ignore Christian scholars.
But it would be hard for a Christian scholar to acknowledge that Luke and Matthew tell different stories about the birth and childhood of Jesus, and that both stories have many signs of legendary storytelling. After all, if those stories were made up, what else might be? So they rationalize. They'll point out that the stories don't actually contradict, so they might both be true, and reflect the different target audiences of the authors. Which is dishonest from a scholarly point of view, but it let's one sleep at night. You don't need the least bit of knowledge about Biblical scholarship to see that the stories are different. But you probably do need to be a nonbeliever, or your mental defenses won't let you see it. So I'm not saying, Christian scholars don't understand the Bible, I'm saying, from their point of view, arriving at certain conclusions in their research might land them in Hell for eternity. So they probably won't reach those conclusions. There's a strong incentive not to. (Then again, your theology may hold that it doesn't matter what happened to Jesus as a child, but then you've moved some distance away from the Christian mainstream.)
There are, I think, five ways to read the Bible, and I've mentioned three of them. You can read it as theology: what does it say about how God wants me to live my life today? You can read it as the Devil does: how can I use this to show that Christianity isn't true? And you can read it as a collection of historical documents: who wrote this, and what does it tell us about actual historical events?
And then you can read the Bible as literature: entertaining and/or insightful stories, legends and poems. And finally you can read the Bible as ancient theology. The difference between modern theology and ancient theology is crucial: Modern theology is about our beliefs, it is about what believers in our time see reflected in the Bible. This changes from decade to decade, and is important for nonbelievers only for what it tells us about Christianity today. (A nonbeliever can't learn about Christianity by reading the Bible oneself, you have to look at how Christians read it.) Ancient theology is about their beliefs, the people of ancient Israel and Palestine, the people who wrote and read these books.
The difference can be dramatic. Early Jews probably believed that there were more than one god in the world, they just didn't worship the others. What we think of as Judaism today was crystallized during and after the Babylonian captivity, by which time most of the Torah had probably already been written. In the same way, much of Christian theology as we know it was formulated after the New Testament had been written. None of the New Testament writers said anything explicitly about the Trinity. Nor do you find much of Paul's theology in the teachings of Jesus - many believe that Paul should be considered the true founder of the Christian religion, and that Jesus was merely his inspiration and focal point.
One New Testament scholar I would recommend is Bart Ehrman. He has written many popular books on early Christianity, and also made several good lecture series for the Teaching Company. Ehrman's focus is on the New Testament (and the Christian Apocrypha) as historical documents and ancient theology. Some of his ideas are controversial to Christians, but they are not speculative. If you look for books about the "historical Jesus", you'll find entire bookshelves of speculation, a separate Jesus for every Jesus author. Ehrman is widely respected, also by Christian scholars, even when they disagree. I consider that a good sign.
Keep in mind though that Biblical scholarship is a difficult subject, so don't attach yourself too strongly to any particular interpretation, by Ehrman or others. For a believer it is important to find the One True Way to understand the Bible. They're putting their souls on the line here. Us nonbelievers do not. We can live with uncertainty. We can live with not knowing for sure what Jesus really believed. We'd like to know, but it doesn't really matter. We can afford to withhold judgement. It is enough for us to know what the plausible alternatives are, and not which one is true. You should know off Bart Ehrman's theory that Jesus was an apocalyptic prophet who predicted the end of time and an earthly Kingdom of God in his own immediate future, but what's most important is that you realize that we can't know any of this for sure. And we don't need to.
If you want to take the historical approach to the Old Testament, you should learn about the Documentary Hypothesis, (also known as the JEDP theory), the idea that the Pentateuch was assembled (redacted) from four different sources, which were written at different times in different places, and represented somewhat different beliefs. This has been the consensus view since the 19th century. The JEDP theory explains why there are two Creation stories, or why God is referred to by different names in the original Hebrew. It is fascinating to read the Bible through the eyes of the Documentary Hypothesis - one verse here is from source J, and then the next is from source E, this reflects a practice of the Northern Kingdom, this of the Southern Kingdom, and so on.
But I was intrigued to come across a lecture series on the Book of Genesis by Gary A. Rendsburg. Rendsburg approaches the Bible as literature, and not so much as historical documents. He believes that the JEDP scholars have focused so much on the sources that they've lost sight of the Pentateuch as a literary whole. If there were different textual sources, the redactor did not just dumbly cut and paste from them, he put considerable thought into the process. He was closer to an author than to an editor.
Rendsburg believes there are themes and stylistic devices in Genesis that make sense only when you see it as a whole. There are patterns in the stories of the Patriarchs, there are recurring themes, such as the lesser person - a barren wife, a youngest son - who is favored and elevated by God, symbolizing the need for the weak Jewish nation to rely on God. And what may seem like contradictions springing from the difference in sources, may actually be intentional literary and theological devices. The Creation story is told twice not because the redactor couldn't decide which one is true, but because he needed both perspectives: The cosmic perspective, which takes the large view, the view of God the all-powerful creator, and the human perspective, which leads into the Adam and Eve story.
I have no opinion on how these books where assembled. But I believe that by reading the Pentateuch as literature, we can properly honor it alongside the other major works of ancient humanity, such as the Illiad and Odyssey, and the Epic of Gilgamesh. We read the Iliad today because it is a powerful story, and a founding work of our culture. We don't care too much how it was put together, we care about the end product, and we read the end product for its own value. This is no less true of the Pentateuch and the rest of the Bible. As theology the Bible is just plain untrue, as historical documents it is a puzzle for scholars - as literature, it is a powerful work of art.
Rendsburg recommends seeking out translations of the Bible that emphasize its literary qualities, such as this one of the Pentateuch by Robert Alter. There are many kinds of Bible translations, and all have their uses. Some focus on capturing the meaning of exact words, others on expressing clearly the ideas behind the words. What Alter aims for is to reproduce the stylistic devices of the Pentateuch, to make it sound more like the original. For instance, the original authors would often use the same word (such as "seed") over and over again in a story, each time having a slightly different nuance of meaning. In English you try to avoid this, you use synonyms to create variation in the text, so translators often replace such ambigous words with ones that are more accurate for their context. Alter tries to retain them. And in the original text you often find sentence after sentence beginning with the word "and". And this is bad english, so modern translators restructure the sentences to avoid it. And Alter retains the "and"'s, and, look, it gives the text a strange and interesting flavor. For instance, from the story of Noah:
That very day, Noah and Shem and Ham and Japheth, the sons of Noah, and Noah's wife, and the tree wives of his sons together with them, came into the ark, them as well as beasts of each kind and cattle of each kind and each kind of crawling thing that crawls on the earth, and each kind of bird, each winged thing. They came to Noah into the ark, two by two of all flesh that has the breath of life within it. And those that came in, male and female of all flesh they came, as God has commanded him, and the Lord shut him in. And the Flood was forty days over the earth, and the waters multiplied and bore the ark upward and it rose above the earth. And the waters surged and multiplied mightily over the earth, and the ark went on the surface of the water. And the waters surged most mightily over the earth, and all the high mountains under the heavens were covered.
Here's the same passage in some other translations: New International Version, English Standard Version, and New American Standard Bible. The effect is somewhat similar to the King James Version, which had a similar literary philosophy, except it is in modern English and incorporates 400 more years of Biblical scholarship. Robert Alter's translation of the Pentateuch is certainly a very beautiful work. And it is full of interesting footnotes.
So that's the literary perspective. As I wrote earlier there are many ways to read the Bible, and the ones that I find relevant are the ones that treat it as historical documents, as literature, or as ancient theology. Of those three, I've come to prefer the literary one. It may seem like I'm belittling the value of the Bible by doing this, that I'm dismissing it as "mere entertainment". What I'm doing is rather to place it on the same bookshelf as the Iliad and other ancient works. I'm honoring it in the way that makes most sense to me as an atheist. I refuse to read the Bible as modern theology. I refuse to scrutinize it for faults (fish, barrel, smoking gun). I choose instead to honor it as the wonderful creative output of some 1000+ years of Hebrew and Mediterranean culture.
As for the "Devil's way" of reading, I understand why some people prefer it. The Bible is to many a symbol of authority, and authority encourages rebellion. And yes, the Bible is full of embarassing passages, (my favourite involves two rampaging bears). But this is a superficial way to read the Bible, and nothing new has been said on that front for a century or so. Do it to confound your literalist friends, but for any other purpose I believe it's a waste of time.
(Update: I just finished Robert Alter's translation of Deuteronomy, the last book of the Pentateuch. What a book! I never noticed before how rhetorically powerful it was. I swear there are sparks flying off the page.)