Since St. Peter of Alcantara (1499–1562) wrote this treatise in 1556 to help people prepare their lives for eternity, readers need not be reminded that sin and eternity hasn’t changed in the last 450 years. St. Peter offers less a practical guide on prayer and meditation than a path to deepening and enriching one’s interior life in order to prepare the soul for its fi nal end. The author does so by providing a series of considerations on the elements of the spiritual life, on the Sacred Passion, and on ways to improve piety (which the author calls “devotion”) and to overcome the difficulties and temptations in its achievement. This book was highly recommended by other contemporary saints including St. Teresa of Avila, whom the author appeared to upon his death. This book is a modernized edition of an English translation from the late 1920s.