An amazing fact is that atheists and free-thinkers seem to be, in fact, very often more knowledgeable of the history and origins of many religious ideas than many of the followers of these faiths are.
A very central reason for this is that atheists and freethinkers often do explore these things thoroughly when they ultimately form opinions of their own in these matters. They often go through this process as adults.
On the other hand, many members of the religious organizations are members simply because of the traditions that were taught to them when they were too young to think for themselves. All too often they have never really deeply personally thought about these matters at all.
However, the high level of religious knowledge that is so common among atheists and freethinkers may be caused also by the fact that many freethinkers still think that they have to know these things to be able to discuss them.
I fear that even for an atheist or freethinker it is all too often very difficult to put Bible to its proper place. It is easy, for example, to forget that the New Testament is in the end just a collection of texts whose only purpose is to propagate a newfangled faith to a maximal effect.
The Old Testament is a collection of old Jewish and middle-eastern folklore, fables, poems, old sayings and wise words. Most of all it is a collection of oral historical tradition. This tradition had been traveling for generations from mouth to mouth and has lost almost all of its value as a historical document on the way.
In a modern western society one can already manage to live one's life quite well without knowing these old stories at all. They have no more intrinsic value as the collections of texts that are put together by the followers of Buddha of Confucius.
Nobody expects that we should know the contents of these old books by heart either, even if knowledge of the general ideas that are included in them is a thing that every civilized person will want to have. In a modern secular society, one does really get quite well along without knowing the exact words that were used by the founders of the Christian faith at all.
Even many of those who are against the organized religions have, however, a notion that one must know the holy books of the Christian faith by hart. However, the Bible was after all a collection of texts that were produced under very different social and cultural circumstances. It was an early and unsuccessful attempt to grasp the meaning of the world. There just was no real knowledge available of the world and its workings.
Its stories were undoubtedly often the best explanations the people of that time had available to them, as no better explanations simply were available at the time. These books had also some worthy models of conduct and morals. They could help people in that long-gone model of undeveloped agricultural society, even if they are now often completely outdated.
The true value of these explanations and morals has steadily diminished. Finally their value has almost wholly disappeared in a modern industrial society. Societies have simply changed and evolved beyond recognition. We have now got tons of real information concerning our world, the inner workings of humans and human societies thanks to the findings of the science.
When one does realize this, one can understand also that the position of this very old book is based solely on the fact that there are still people who think that these books can still be used as a model of morality and behavior in general. They do believe in this even in our extraordinarily different societies over 2000 years later.
There simply is no real need to discuss the value of any of individual stories included in these old books. This is true especially when one does realize that the New Testament is just a vehicle for the advancement of a brand new ideology.
The New Testament was produced by people who had a glowing belief in that ideology. They tried to convince all others of the value and power of this newfangled ideology with the help of this book.
Of course, there is still a need to know the general outline of the major stories that are included in the Bible. It is a central historical document that has had a major impact in our societies. However, we do not commonly read many other historical documents word-by-word either, but we are satisfied with summaries of their content.
Even this knowledge is really needed in the field of the cultural history only. Our modern western culture has already lost almost all connections with this book.
There was once a time when you simply could not understand much of the then current literature without knowing and understanding the references to Biblical matters that were included in them. If one is a friend of old Victorian literature one has still a good reason to read the Bible.
Happily, one is really hard pressed to find any direct biblical references in the contemporary literature. One does not really need to read the Bible even for this reason anymore. The Bible is now just a historical document that does record the ideas and history of a small and quite insignificant Middle-eastern nation. If one is interested in the history of small and insignificant middle-eastern nations, the Bible is of course a must read.
However, if one is not interested in the early history of the Middle East and the history of the ideas that were later used for good measure in Judaism and Christianity, the Bible has really very little to give.
In fact in my mind there are no compelling reasons to read the Bible in its entirety anymore. However, there is naturally intellectual curiosity and a need to know what these Christians are talking about. Still, a general knowledge of the ideas presented in it and on the ideologies that are based on it is quite enough for most of us, I think.
There are quite similar incentives to read, for example, Iliad and Odysseus or Bhagavad Gita or Quran also if one finds an interest in the holy books of religions.
(This little essay was totally refurbished in 20th of March, 2012)