What's The Paradigm We're Working From?

On being beaten by two young men for being a Satanist:

"My allegiance is to Satan and I hate Christianity, Judaism and Islam, but I don't hurt anyone," Mr. Romano said. "I take out my anger in mosh pits and S-and-M clubs. I think it's ironic that the Christians got violent with the Satanist."

His mother, Debbie Romano, 48, said, "I'm a Christian, but he went the other way; I don't understand his beliefs, but he doesn't hurt nobody."

Please elucidate, Mr. Romano: why exactly is it "ironic"?