Between ages 20 and 50, the average person spends about 20,000 hours—over 800 days—eating. Our daily schedules are often planned around mealtimes. Business deals are cut among people who "do" lunch together. We have TV dinners, fast-food drive-up windows, and tailgate parties.

Eating is also a problem in our culture. In one poll, 40 percent of the respondents said that "getting fat" was what they fear most in the world. This may be one reason that each day approximately 65 million Americans are dieting, and the sales of diet books outrank all other books on the market except for the Bible.

But few books, even those by Christians, spend much time on the topic of gluttony. In Whatever Became of Sin? (1973), Karl Menninger described how cultural, psychological language has replaced moral language in our culture. The dieting industry, even the Christian version, talks a lot about nutrition and eating disorders while sidelining gluttony.

This is a surprise, for gluttony was for centuries considered a chief sin to monitor, one of the seven deadly sins. It is also a loss, for the insights of the early Christian monks on gluttony, and its corollary, fasting, are more relevant than any dieting fad.

Eating, of course, is crucial in biblical narratives. Our first parents plunged the human race into sin by violating a prohibition against eating. The Hebrews were given a sense of identity in a meal that signifies the defining moment in their history. The second Adam was victorious over a temptation involving bread. Christians celebrate their life together in Christ around a family meal initiated by Jesus—one that anticipates an eschatological banquet marking the consummation of history. Add to these all of the stories many of ...