I've noticed for the past ten years an increasing tendency among young people, thoughtful ones in particular, toward what I have come to describe as Biblical atheism. I realize that this is a very unusual turn of phrase, and that I owe some explanation to the reader for it. To understand what I mean by that, let's consider what is meant by the phrase "Biblical Christianity" as a starting point.
There are many different churches which claim to hold to a Biblical Christianity; what is common to all those churches is that they take the justification for their beliefs about God and their religious practices from the Bible, generally the Western canon used by the Roman Catholic church during the Middle Ages minus a few books. Despite the common starting point, the churches which hold to what they describe as Biblical Christianity quickly move off in very different directions. The common point of divergence is on the subject of how to read the Bible correctly. Sometimes churches will only differ on how a few verses are to be read; sometimes they propose completely different principles for reading the entire Bible and come to mutually exclusive positions which are very far apart.
For example, some churches (like the one in which my grandfather was a pastor) take the position that the Bible should be read primarily literally, but with a few exceptions. Other churches take the position that the Bible should be read primarily allegorically, but with a few exceptions. To see the advantages and disadvantages of these two positions, we can take a look at a passage in the Bible often brought up by young atheists. For the Biblical literalist, Elisha's calling of the bears to maul the 42 youths is completely justified. For those who wish to read the book as allegorical, the question of whether the act was justified or not is largely irrelevant; the point is something completely different from the described events which are at best loosely connected to them.
The advantage for the Biblical literalists is that the interpretation requires little to no intellectual gymnastics to explain; those intellectual gymnastics are of course precisely what makes the allegorical reading a hard sell to many people. The purely allegorical reading often seems far too distant from the text to be a plausible reading of it. The advantage for the the Biblical allegoricalists is that the interpretation allows them to completely sidestep the issue of Elisha being a big meanie who called bears out to maul a bunch of youngsters. After all, that was not the point of the passage, in their view.
So how does all this help us understand Biblical atheism? The Biblical atheist, like the Biblical Christian, takes their justification for their beliefs about God and Christian religious practices from the Bible, generally the Western canon used by the Roman Catholic church minus a few books. To see a clear example, take a look at the video in which Penn Jillette explains why he thinks atheism follows from reading the Bible.
As you can see if you read my commentary on the video, I disagree with Penn Jillette that atheism follows from reading the Bible; I propose that just as the Bible is not compelling evidence of God's existence, neither is it compelling evidence of the lack thereof. That said, I do think that Biblical atheism is completely understandable in light of the two modes of Biblical interpretation typically offered to young people as they begin to learn about the Bible from Christians.
The Biblical atheist is, I think, completely justified in finding the purely allegorical reading of difficult passages implausible. It does seem like an attempt to dodge the question of God's justice in empowering His prophet to have bears maul forty-two youths. That is a completely appropriate question to ask, and they deserve a better answer than, "Well that's not the point. Look over here at this stuff it prefigures in the New Testament and the End Times."
At the same time, the literal reading will strike the average young person in the post-industrial West as horribly immoral on God's part. A severe physical punishment for not recognizing God's messengers or God's message is not something that would have been imposed on them by their parents whom they consider to be loving, so how could a loving God do such a thing? In light of the circumstances, it is completely understandable that they would find it hard to believe that a loving God exists.
The Biblical atheist and the Biblical Christian start from the same point, but reach very different conclusions based on applying the same interpretive approaches. The Biblical Christian sees the advantages of their favored hermeneutic and find the resulting reading plausible; the Biblical atheist sees the disadvantages of both the literal and allegorical reading and finds both readings implausible.
In an interesting turn of events, it seems that while atheism does not
rationally follow from reading the Bible, it may be that Biblical
atheism does in practice often follow from exposure to Biblical Christianity.