I know myself, and I have such a sense of religion that I shall never do anything which I would not do before the whole world; but I am alarmed at the very thoughts of being in the society of people, during my journey, whose mode of thinking is so entirely different from mine (and from that of all good people). But of course they must do as they please. I have no heart to travel with them, nor could I enjoy one pleasant hour, nor know what to talk about; for, in short, I have no great confidence in them. Friends who have no religion cannot be long our friends.

Letter to Leopold Mozart (Mannheim, 2 February 1778), from The letters of Wolfgang Amadeus Mozart, 1769-1791, translated, from the collection of Ludwig Nohl, by Lady [Grace] Wallace (Oxford University Press, 1865, digitized 2006) vol. I, # 91 (p. 164)

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