As an American, your friend should realize that while he has the right to believe in what he chooses to and practice it freely, so do other people.
Simply hearing someone say it is not going to send you to hell. So really he just needs to stop being uptight.
I'd think that relgious people would be more open-minded than non-religious, seeing as they believe in things with little to no evidence of existence, but it's funny how so many deeply religious people are sworn to one mindset for life.
(Funny enough, this is coming from a christian.)