Sanctifying grace is, of course, one of the supreme realities for the Christian. Its loss is his only authentic tragedy ; its possession in his beatitude. Given its importance, it is surprising how little, really, the average Christian knows about grace, and how little has been done to repair his ignorance. Constant reference is made to it in the books he reads and the sermons he hears, but little is written or said about the reality itself. He has long needed just such a responsible explanation of grace as Father Gleason has provided in this stimulating study. Here, for example, one will find the evolving concept of grace in the Old Testament, the developing awareness among the Fathers of just what the "gift of divine life" meant on the part of both God and man and the massive contribution to this same understanding effected by the Council of Trent, set in contrast with the view of grace presented by the first Protestant Reformers. The qualities which have earned Father Gleason an international reputation are clearly visible in this present work as well - a sense of historical development, a sure grasp of the central theological tradition, and an awareness of how relevant theologicals realities are to the psychic needs of modern man.