Insulting someone because of their beliefs or race is flaming, and the people that do it are morons. When was the last time you took a moron's opinion seriously? They aren't worth paying attention to.
However, a rule against "blasphemy" is ridiculous. I am completely irreligious. My very existence in some religions is "blasphemy". If someone thinks that I lack morals because I don't derive them from god, I'm not going to stop them from telling me. It doesn't hurt me. I'll probably try to change their mind about it. Similarly, if I, a
heliocentrist, also blaspheme that the (now) saint, "Mother" Theresa was an evil thanatophile with good PR skills, it doesn't hurt you. If you think otherwise, try changing my mind instead of silencing me. We are distinguished from other animals in that we possess the ability to communicate at (relatively) high levels. Arguing and disagreeing about shit, or perhaps changing our minds, is what makes us human. Don't take that away.
If you're so insecure in your beliefs that you can't attempt to correct another person's bad impressions of what you believe, then that is your problem. If someone else is so insecure in their beliefs that they try to ridicule yours, then that is their problem. There isn't any need to silence anyone.
