Paul Tillich was one of the greatest theologians of the 20th century, the "father of existential theology" was he. And yet, when he was asked to define what a Christian is, he said "Oh, that's easy; a Christian is simply one beggar telling another beggar where to find food."
The Christian Church in the 21st century does not see itself as beggars telling other beggars where to find food. Rather, I fear that we see ourselves as being right. We have the right theology, so that makes the others wrong. We have the right liturgy, or the right political opinions, or our members act in the right way. We're not beggars! We're not even sinners! We used to be, but not anymore. And that sort of attitude is not only a myth, but it repels the people whom Jesus wants us to reach out to…the ones who know the secret; that Jesus' primary purpose in coming to the world was not to tell us to straighten up and fly right. It was to tell us that we were beggars, and he was the food.