If the Christian doesn't get reality right, he loses effectiveness in this life. If the non-Christian doesn't get reality right, he loses much in this life, and everything and the next one. As Jesus put it, "What does it profit a man if he gains the whole world and loses his soul?"
Greg KouklPeople are tempted to think (understandably) that if God were really good He'd never allow any evil in the world at all. But I don't think a perfectly good God would never permit any evil, and neither would others, I wager, if they thought about it. Rather, I think that a good God always prevents suffering and evil unless He has a good reason to allow it. That's the crux.
Greg Koukl