Abstract
Pope Leo XIII’s encyclical Divinum Illud Munus offers a poignant reflection on the person and work of the Holy Spirit. Among the Holy Spirit’s marvelous works is His indwelling within the souls of the just. Leo writes that the union between the Christian soul and the indwelling Spirit differs conditione tantum seu statu (only in degree or state) from that union by which the saints are united to God in heaven. If this is true, then the soul’s union with God on earth via the divine indwelling is already a foretaste of that beatitude in which it will enjoy God for all eternity in heaven. This thesis examines the reality of the divine indwelling as expounded in the various loci of theology (chapter I), seeks to understand the manner of the divine indwelling, i.e. how it is that the three Divine Persons can truly dwell within the soul (chapter II), and compares the life of the soul in grace here on earth to the life of the soul who enjoys the vision of God face-to-face in heaven (chapter III). The result of this investigation will reveal just how closely related are the heavenly and earthly realms due to the supernatural work of the Holy Spirit as well as the implications of this for the spiritual life of Christians (chapter IV and conclusion).