Even though I don't believe in Christianity (or any religion for that matter), I think it's acceptable to let people believe what they want to believe. There's no way that any Christian could prove that god exists, but a counter argument to that is that if they did know he existed, there would be nothing to believe in and there would be no point to the religion. One thing I don't stand for is richards telling a religious person/people that they shouldn't have a religion and that they are stupid for having one. It's their choice, not yours, and if you think that believing in a god is ridiculous, surely the fact that they believe in god is punishment to themselves, and not something you should have to bring up?
It's totally stuffty.