Leszek Kolakowski, via Alan Jacobs:

Doubt may be considered one of the consequences of original sin, but it also protects us against its more deleterious effects. It is important for us to be uncertain about the deep motives for our own deeds and the grounds of our convictions, since this is the only device that protects us against an old justifying fanaticism and intolerance. We should remember that the perfect unity of man is impossible, otherwise we would try to impose this unity by any means available, and our foolish visions of perfection would evaporate in violence and end in a theocratic or totalitarian caricature of unity which claimed to make the Great Impossible an actuality. The greater our hopes for humanity, the more we are ready to sacrifice, and this too seems very rational. As Anatole France once remarked, never have so many been murdered in the name of a doctrine as in the name of the principle that human beings are naturally good. […]

There are reasons why we need Christianity, but not just any kind of Christianity. We do not need a Christianity that makes political revolution, that rushes to cooperate with so-called sexual liberation, that approves our concupiscence or praises our violence. There are enough forces in the world to do all these things without the aid of Christianity. We need a Christianity that will help us move beyond the immediate pressures of life, that gives us insight into the basic limits of the human condition and the capacity to accept them, a Christianity that teaches us the simple truth that there is not only a tomorrow but a day after tomorrow as well, and and that the difference between success and failure is rarely distinguishable. We need a Christianity that is not gold, or purple, or red, but grey.