Whether I wasted them or not is for you to judge. I certainly did not hear any more of the sermon. I was thinking; and the starting-point of my thought was the question, ‘How can he? How can he of all people?’ For I knew the preacher’s own home pretty well. In fact, I had been lunching there that very day, making a fifth to the Vicar and the Vicar’s wife and the son (Royal Air Force) and the daughter (Auxiliary Territorial Service), who happened both to be on leave. I could have avoided it, but the girl had whispered to me, ‘For God’s sake stay to lunch if they ask you. It’s always a little less frightful when there’s a visitor.’ [Sorry, you'll have to read the essay for the sordid details of lunch at the vicar's!]
.... The memory of that lunch worries me during the last few minutes of the sermon. I am not worried by the fact that the Vicar’s practice differs from his precept. That is, no doubt, regrettable, but it is nothing to the purpose. As Dr Johnson said, precept may be very sincere (and, let us add, very profitable) where practice is very imperfect, and no one but a fool would discount a doctor’s warnings about alcoholic poisoning because the doctor himself drank too much. What worries me is the fact that the Vicar is not telling us at all that home life is difficult and has, like every form of life, its own proper temptations and corruptions. He keeps on talking as if ‘home’ were a panacea, a magical charm which of itself was bound to produce happiness and virtue. The trouble is not that he is insincere but that he is a fool. He is not talking from his own experience of family life at all: he is automatically reproducing a sentimental tradition — and it happens to be a false tradition. That is why the congregation have stopped listening to him.
C.S. Lewis, "The Sermon and The Lunch" (1945) included in God in the Dock (Eerdmans, 1970) 283-284.