A comment by FunkyDerek really hit my like a lightning bolt. He said of a Christian's morals, "your morals are not high. They are among the basest, most nefarious morals I have ever encountered. They are founded, not on any understanding of human nature, or on concern for individuals or society, but on the mythology and law codes of ancient barbarians."
Dave, I'm glad I could give you a different perspective on things. As this thread seems to have generated some interest, I'd like to expand on my original comments.
It may seem strange to some that I consider those who unquestioningly follow the Bible to be immoral. After all, they don't steal, they don't murder, they don't lie, they will help those in need, all admirable traits. But stealing isn't wrong because God carved it on a rock three thousand years ago. Stealing is wrong because it means taking something of value that belongs to someone else. It means illegitimately depriving someone of the fruit of their labour. People who don't steal simply because the Bible prohibits it cannot rightly be called moral people. They will certainly have an appearance of morality, and will often behave like a very good approximation of a highly moral person. Isn't that enough, though? If everyone behaved like that, the world would be fine, right?
The problem comes when the good advice and sensible laws are mixed up with all sorts of useless and dangerous beliefs. Eating pork (but not beef) is an abomination. Menstruating women are unclean, homosexuals should not be tolerated. No work should be done on a Saturday, on penalty of death. Obviously, if the Bible is the source of your morality, you may very well end up following some of its bad advice along with the good. How can you distinguish if you simply accept everything that's written in the Bible?
The same is true no matter what book you use as a moral guide. With no understanding of what makes an action good or evil, those who blindly follow sacred texts are not equipped to deal with a changing world with conflicting rules or with people who follow a different sacred text - or none at all.
Morals need to be based on reality - they need to acknowledge human nature and they need to provide principles by which we can make decisions. It's not enough to ask "What would Jesus do?" We need to ask "What should I do?" and we need to have a good way of answering that.