If each side had been frankly contending for its own real wish, they would all have kept within the bounds of reason and courtesy; but just because the contention is reversed and each side is fighting the other side’s battle, all the bitterness which really flows from thwarted self-righteousness and obstinacy and from the accumulated grudges of the last ten years is concealed from them by the nominal or official "Unselfishness" of what they are doing or, at least, held to be excused by it.
C.S. Lewis, The Screwtape Letters
religion