I've been reading unChristian by David Kinnaman of the Christian research group, The Barna Group. Here's another challenging quote (see the monthly quote on side column).
The first error that christians make is coming to the wrong conclusion. God's judgments about people are perfect; ours are not. When Christians reach the wrong verdict, it is typically because of our own biases, assumptions, or stereotypes about others. Our superficiality gets the best of us. One Christian I talked to recently said, "Yeah, I know what you mean about stereotypes. When I see a person who is tattooed or pierced up, I try not to judge them based on their outward appearance. I realize that their appearance is probably just a symptom."
I was shocked. Did you notice what he was saying? He may as well have said, "I wouldn't judge based on outward appearance, but there is something wrong with these people on the inside." Do you see how subtle judgment can be? It creeps up on us and drips out of our conversations and attitudes.