The Holy Ghost in us through Mary
Through the sacrament of Confirmation, we receive the fullness of the gifts of the Holy Ghost, and He himself fills our souls and illuminate them with the fire of His Love, making us participate in the Love with which God loves Himself in the mystery of the Holy Trinity. According to Saint Grignion de Montfort (True Devotion to the Blessed Virgin Mary, no. 20) the Holy Ghost becomes fruitful in Mary and produces his masterpieces only in her and through her (the holy humanity of Our Lord, the sanctification of souls). At Pentecost, she is in the midst of the apostles, and according to an ancient tradition, the gifts of the Holy Ghost are given to them through her. Our Pentecost is the reception of the sacrament of Confirmation and the gifts of the Holy Ghost are given only through her (like all other graces).
The profound reason for this action of the Holy Ghost in Mary and through Mary lies in His very relationship with her. The Fathers of the Church call her the sacrarium Spiritus Sancti; since the Middle Ages, she has been commonly invoked as the Spouse of the Holy Ghost. The Holy Ghost is the gift of the Father and the Son. St. Thomas explains that God wants to give Himself as much as He can to a creature. This gift is the Holy Ghost Himself. However, after Original Sin, the obstacle lies in the vessel itself which is more or less obstructed by actual sins and wounds of Original Sin. Only once during the whole history of humanity is the donum Dei altissimi received completely and does not meet any obstacle. Only once is it received without the slightest hesitation, because only once does the Holy Ghost find the vessel which He is entering to be totally pure and immaculate.
In other words, in all of history, it was only the soul of the Immaculata that the Holy Ghost was able to transform completely in such a way that she was and is abandoned entirely to His will and inspirations. Therefore, all her thoughts, words, actions are in a way more the thoughts, words and actions of the Holy Ghost than her own. She will never think of anything other than what the Holy Ghost makes her think, she will only speak the words of God, etc. She is somehow the visible presence of the Holy Ghost in the world, His sanctuary, His tabernacle, His Spouse. Her greatness consists in the fact that the human person Mary, the daughter of St. Anne and St. Joachim, is, since her Immaculate Conception, so intimately linked to the Third Person of the most Holy Trinity that she is more the presence of the Holy Ghost in the world than she is the presence of herself.
In conclusion: where Mary is, there is the Holy Ghost. On earth, the Holy Ghost is where Mary is. Therefore, to the extent that we are consecrated to the Immaculata, the Holy Ghost will invade us with His gifts and make the ineffaceable character of the sacrament of Confirmation blossom.