Sex before marriage. Most religious people are not permitted to engage in it, but most of them do anyways. Some people say it's fun, others say it's immoral. It's considered a grave sin in
Christianity, Judaism, and Islam. In some countries, it is punishable by
death (Primarily
muslim countries) but in most developed countries, it's perfectly legal.
James: I waited until
marriage to have sex, so as soon as my wife
saw how
small my dick was, she divorced me
Joe: Damn dude, why didn't you just show her?
James: I'm a Christian and we can't have premarital sex