Morality
Religion cannot be used as a basis for moral behaviour because it implies a moral superiority. Any time you feel superior to anybody for any reason, you have succumbed to vanity. Ah...Vanity, vanity. And what is vanity but selfishness? And isn't that the main selling point of Western religion? Selfishness? Save yourself. Morality only truly works when you only use it as a basis of how you should live, not as others should live.