S., a clever and truthful man, once told me the story of how he ceased to believe. On a hunting expedition, when he was already twenty-six, he once, at the place where they put up for the night, knelt down in the evening to pray -- a habit retained from childhood. His elder brother, who was at the hunt with him, was lying on some hay and watching him. When S. had finished and was settling down for the night, his brother said to him: 'So you still do that?' They said nothing more to one another. But from that day S. ceased to say his prayers or go to church. And now he has not prayed, received communion, or gone to church, for thirty years. And this not because he knows his brother's convictions and has joined him in them, nor because he has decided anything in his own soul, but simply because the word spoken by his brother was like the push of a finger on a wall that was ready to fall by its own weight. The word only showed that where he thought there was faith, in reality there had long been an empty space, and that therefore the utterance of words and the making of signs of the cross and genuflections while praying were quite senseless actions. Becoming conscious of their senselessness he could not continue them.

Leo Tolstoy