Dude, there are some many Christians out there who haven't read that Epistle, aren't that "knowledgeable" about the Bible and the more arcane elements of Christian theology, and do believe that the apocalypse will happen in their lifetime. I mean, seriously, have you already forgotten the Left Behind series? That was all over this! (And you can't call them non-Christians, either; as long as they believe that Jesus Christ is their Lord and Savior and died for their sins and now sits in Heaven at the right hand of God the Father, they're Christian. Maybe not your flavor of Christian, but they're Christian.)