4 Having thus paid the due tribute of faith and worship owing to the Blessed Trinity, and which ought to be more and more inculcated upon the Christian people, we now turn to the exposition of the power of theHoly Ghost. And, first of all, we must look to Christ, the Founder of the Churchand the Redeemer of our race. Among the external operations of God, the highestof all is the mystery of the Incarnation of the Word, in which the splendour ofthe divine perfections shines forth so brightly that nothing more sublime caneven be imagined, nothing else could have been more salutary to the human race.Now this work, although belonging to the whole Trinity, is still appropriatedespecially to the Holy Ghost, so that the Gospels thus speak of the BlessedVirgin: "She was found with child of the Holy Ghost," and "thatwhich is conceived in her is of the Holy Ghost" (Matt. i., 18, 20). Andthis is rightly attributed to Him who is the love of the Father and the Son,since this "great mystery of piety" (1 Tim. iii., 16) proceeds fromthe infinite love of God towards man, as St. John tells us: "God so lovedthe world as to give His only begotten Son" (John iii., 16). Moreover,human nature was thereby elevated to a personal union with the Word; and thisdignity is given, not on account of any merits, but entirely and absolutelythrough grace, and therefore, as it were, through the special gift of the HolyGhost. On this point St. Augustine writes: "This manner in which Christ wasborn of the Holy Ghost, indicates to us the grace of God, by which humanity,with no antecedent merits, at the first moment of its existence, was united withthe Word of God, by so intimate a personal union, that He, who was the Son ofMan, was also the Son of God, and He who was the Son of God was also the Son ofMan" (Enchir., c. xl. St. Th., 3a., q. xxxii., a. 1). By the operation ofthe Holy Spirit, not only was the conception of Christ accomplished, but alsothe sanctification of His soul, which, in Holy Scripture, is called His"anointing" (Acts x., 38). Wherefore all His actions were"performed in the Holy Ghost" (St. Basil de Sp. S., c. xvi.), andespecially the sacrifice of Himself: "Christ, through the Holy Ghost,offered Himself without spot to God" (Heb. ix., 14). Considering this, noone can be surprised that all the gifts of the Holy Ghost inundated the soul ofChrist. In Him resided the absolute fullness of grace, in the greatest and mostefficacious manner possible; in Him were all the treasures of wisdom andknowledge, graces gratis datae , virtues, and all other gifts foretold in theprophecies of Isaias (Is. iv., I; xi., 23), and also signified in that miraculous dove which appeared at the Jordan, when Christ, by His baptism, consecrated its waters for a new sacrament. On this the words of St. Augustine may appropriately be quoted: "It would be absurd to say that Christ received the Holy Ghost when He was already thirty years of age, for He came to His baptism without sin, and therefore not without the Holy Ghost. At this time, then (that is, at His baptism), He was pleased to prefigure His Church, in which those especially who are baptized receive the Holy Ghost" (De. Trin. 1., xv., c. 26). Therefore, by the conspicuous apparition of the Holy Ghost over Christ and by His invisible power in His soul, the twofold mission of the Spirit is foreshadowed, namely, His outward and visible mission in the Church, and His secret indwelling in the souls of the just.
Source: Divinum Illud Munus (Vatican.va)