The New York Times bestselling author and senior fellow at the Discovery Institute blends science and religion in this thoughtful guide that teaches modern believers how to use the leading wellness trend today—intermittent fasting—as a means of spiritual awakening, adopting the traditions our Christians ancestors practiced for centuries into daily life.

Wellness minded people today are increasingly turning to intermittent fasting to bolster their health. But we aren’t the first people to abstain from eating for a purpose. This routine was a common part of our spiritual ancestors’ lives for 1,500 years.

Jay Richards argues that Christians should recover the fasting lifestyle, not only to improve our bodies, but to bolster our spiritual health as well. In Eat, Fast, Feast, he combines forgotten spiritual wisdom on fasting and feasting with the burgeoning literature on ketogenic diets and fasting for improved physical and mental health. Based on his popular series “Fasting, Body and Soul” in The Stream, Eat, Fast, Feast explores what it means to substitute our hunger for God for our hunger for food, and what both modern science and the ancient monastics can teach us about this practice.

Richards argues that our modern diet—heavy in sugar and refined carbohydrates—locks us into a metabolic trap that makes fasting unfruitful and our feasts devoid of meaning. The good news, he reveals, is that we are beginning to resist the tyranny of processed foods, with millions of people pursuing low carb, ketogenic, paleo, and primal diets. This growing body of experts argue that eating natural fat and fasting is not only safe, but far better than how we eat today.

Richards provides a 40-day plan which combines a long-term “nutritional ketosis” with spiritual disciplines. The plan can be used any time of the year or be adapted to a penitential season on the Christian calendar, such as Advent or Lent.

Synthesizing recent science with ancient wisdom, Eat, Fast, Feast brings together the physical, mental, and spiritual benefits of intermittent fasting to help Christians improve their lives and their health, and bring them closer to God.