The early Christian monks of Egypt, Syria, and Palestine were the spiritual heroes of their age—fleeing the security of civilization for the desert, where they sought God in lives of prayer, contemplation, and radical simplicity. This book is a portable collection of their teachings, and those of their contemplative contemporaries, ranging from the fourth through the eleventh centuries.

It is arranged to the traditional model of three ascending "books": Praktikos (practice), Theoretikos (theory), and Gnosis (knowledge). Each book consists of 100 "sentences"—aphorisms or thoughts. Each sentence is intended to be read and meditated upon for an entire day—just as the monks themselves might have done as they went about their work.