This is from Greg Boyd's book Myth of a Christian Nation.

"When people assume the position of moral guardians of the culture, they invite---they earn!---the charge of hypocrisy. For all judgement, save the judgement of the omniscient and holy God, involves hypocrisy. Whenever we "eat of the tree of the knowledge of good and evil"---this is, whenever we find some element of worth, significance, and purpose in contrasting ourselves as "good" with the others we deem "evil"--we do so in a self-serving and selective manner. We always bend the tree, as it were, to our own advantage and, as a result, we do the exact opposite of what Jesus taught us to do. Instead of seeing our own sins as worse than others, we invariably set up a list of sins in which our sins are deemed minor while the other people's sins are deemed major. We may have dust particles in our eyes, we reason, but at least we don't have tree trunks like "those people." Unlike the tax collector who made no moral claims for himself, we thank the Lord we are not like other people just as the Pharisee did (Luke 18:9-14)."