Sundays after church, Kay Wilson normally can be found in her Arcadia, California, kitchen preparing a home-cooked meal for her pastor-husband, her two daughters, and their husbands. Yet for the 40 days before Easter last year, Wilson served but did not eat her home-baked bread and flame-grilled steaks. In order to draw closer to God and to pray for a nationwide spiritual awakening, she lived on fruits and vegetables.

Wilson confesses that her partial fast was more a struggle with self-control than a saintly spiritual high. "I'd give anything to eat a piece of meat or cheese," says Wilson, who admits to gravitating toward food when feeling stressed. So when she found herself scheduled to speak at a women's conference during her 40-day fast, Wilson was overwhelmed by the breakfast buffets and abundance of snacks. "It was my inclination to say, 'Poor me,' but instead I said, 'Lord, you are my portion.' " Despite days of doubt and temptation, Wilson says she learned to feast at God's banqueting table. "There is something about the discipline," she says, reflecting on her fast; "it was the most meaningful Holy Week I had ever experienced."

Wilson joins the growing ranks of American evangelicals rediscovering fasting, among the most ancient and rigorous of spiritual disciplines. The contemporary reinterpretation of fasting (few latter-day fasters end all nourishment) has unexpectedly placed fasting evangelicals near the frontlines of alternative spiritual expression.

As with early Christian ascetics under Constantine in the fourth century, some evangelicals are looking for a way to separate themselves from cultural Christianity. Within the past five years, hundreds of thousands of Christians have attended conferences and purchased ...