Paula Kirby justifies converting from a devout Christian to an atheist:
What happened was four little words: “How do I know?”
One of the things that had struck me during my Christian years was just how many different Christianities there are. Not just the vast number of different sects and denominations (over 38,000 by one reckoning), but the huge amount of difference between individual Christians of the same sect or denomination, too. The beliefs and attitudes of an evangelical, biblical, literalist Christian compared with a liberal Christian are so wildly different that we might almost be dealing with two completely different religions …
Some of us knew that God wanted us to respond to other people’s shortcomings with tolerance and forbearance and humility; others knew that he wanted sin to be made an example of, to be held up and publicly rebuked. … This is why subjective experience cannot tell us anything about God. Knowing what kind of god someone believes in tells us a great deal about that person – but nothing whatsoever about the truth or otherwise of the existence of any god at all.
The Dish 