The Book of Genesis (comics) was brought up Catholic, and thus is familiar with the more common Bible stories, but gave up the Catholic faith when he was 16. He went through a phase when he was 15 where he "[went] to church a lot, receiving communion, saying the Rosary, praying", but when he started to scrutinize it, "it just fell apart so quickly." Crumb says he is spiritual, gnostic, and not an atheist; he is "interested in pursuing and understanding the spiritual nature of things." He believes there is a God, but "I don't believe [the Book of Genesis is] the Word of God.
The Yale Book of Quotations songs, political slogans, proverbs, and television catchphrases. There is also coverage of traditional literary sources. There are, for example, 400 quotations from the Bible, 106 quotations from Charles Dickens, 127 quotations from T. S. Eliot, 153 quotations from Mark Twain, and 455 quotations from William Shakespeare. This coverage is less extensive than that offered by "Bartlett's", which provides 1,642 quotations from the Bible and 1,906 from Shakespeare. "The Yale Book of Quotations"' introduction also exhaustively describes the editor's attempts at research to identify many famous quotations, trace them to their original sources as far as possible, and record those sources