The Three Ages of the Interior Life is one of the greatest works ever written on the spiritual life, and it is the masterpiece of Father Reginald Garrigou-Lagrange, O.P. (1877-1964), whom many consider the greatest theologian of the 20th century. First published in English in 1948, The Three Ages of the Interior Life has been out of print for many years, yet it is widely known and highly esteemed by those fortunate enough to own a set. In this classic work Fr. Garrigou-Lagrange has given a complete and systematic explanation of ascetical and mystical theology, and in the process he has explained all aspects of the supernatural life of grace in the soul and shown how Sanctifying Grace, along with the Supernatural Virtues of Faith, Hope and Charity and the Seven Gifts of the Holy Ghost, are meant to grow and develop as a "supernatural organism" in every Christian soul. Basing his teaching squarely on the principles of St. Thomas Aquinas and St. John of the Cross, Fr. Garrigou-Lagrange also draws freely from Sacred Scripture and Tradition, as well as from the teachings of the great Saints, Doctors of the Church and other Catholic mystical writers. Composed of 95 chapters, this two-volume work covers a myriad of topics, yet it is no mere random collection of doctrinal subjects. Rather it is a work of unity, structure and purpose, and it is extremely valuable as a roadmap for understanding the rich but often disorganized writings of the Saints and other mystical writers. Fr. Garrigou-Lagrange explains precisely in what sanctity consists and clearly expounds and defends the ancient Christian tradition that all Christians are called to holiness. The title of this work refers to the classic division of the spiritual life into three successive states: The Purgative Way, the Illuminative Way and the Unitive Way. Showing that the faithful Christian's life of ascetical practices is meant to flower into the mystical life, he clearly distinguishes between, on the one hand, those graces of the mystical life that are in themselves extraordinary (such as visions and ecstasies), and on the other hand, that grace which is often considered extraordinary (not common among souls) but which is in fact in the normal way of sanctity, namely, infused contemplation. In particular, he propounds the thesis that infused contemplation of the mysteries of Faith-and the resulting union with God-are in the normal way of sanctity and are also morally necessary for holiness. Infused contemplation is thus clearly presented, not as a peripheral phenomenon in the spiritual life, nor as something reserved for those in the cloister, but rather as a gift which any Christian may well desire and beseech of God, since it is the usual way of reaching eminent sanctity.