From Dom Guéranger's The Liturgical Year.
The object which the Church has in view by her liturgical year is the leading of the Christian soul to union with Christ, and this by the Holy Ghost. This object is the one which God Himself has in giving us His own Son to be our mediator, our teacher, and our Redeemer, and in sending us the Holy Ghost to abide among us. To this end is directed all that aggregate of rites and prayers which we have hitherto explained: they are not a mere commemoration of the mysteries achieved for our salvation by the divine goodness, but they bring with them the graces corresponding to each of those mysteries; that thus we may come, as the apostle expresses it, ‘to the age of the fullness of Christ.’
As we have elsewhere explained, our sharing in the mysteries of Christ, which are celebrated in the liturgical year, produces in the Christian what is called in mystic theology the illuminative life, in which the soul gains continually more and more of the light of the Incarnate Word, who, by His examples and teachings, renovates each one of her faculties, and imparts to her the habit of seeing all things from God’s point of view. This is a preparation which disposes her for union with God, not merely in an imperfect manner and one that is more or less inconstant, but in an intimate and permanent way, which is called the unitive life. The production of this life is the special work of the Holy Ghost, who has been sent into this world that He may maintain each one of our souls in the possession of Christ, and may bring to perfection the love whereby the creature is united with its God.
In this state, in this unitive life, the soul is made to relish, and assimilate into herself, all that substantial and nourishing food which is presented to her so abundantly during the Time after Pentecost. The mysteries of the Trinity and of the blessed Sacrament, the mercy and the power of the Heart of Jesus, the glories of Mary and her influence upon the Church and souls—all these are manifested to the soul with more clearness than ever, and produce within her effects not previously experienced. In the feasts of the saints, which are so varied and so grand during this portion of the year, she feels more and more intimately the bond which unites her to them in Christ, through the holy Spirit. The eternal happiness of heaven, which is to follow the trials of this mortal life, is revealed to her by the feast of All Saints; she gains clearer notions of that mysterious bliss, which consists in light and love. Having become more closely united to holy Church, the bride of her dear Lord, she follows her in all the stages of her earthly existence; she takes a share in her sufferings; she exults in her triumphs. She sees, and yet is not daunted at seeing, this world tending to its decline, for she knows that the Lord is nigh at hand. As to what regards herself, she is not dismayed at feeling that her exterior life is slowly giving way, and that the wall which stands between her and the changeless sight and possession of the sovereign Good is gradually falling to decay; for, it is not in this world that she lives, and her heart has long been where her treasure is.
Thus enlightened, thus attracted, thus established by the incorporation into herself of the mysteries wherewith the sacred liturgy has nourished her, as also by the gifts poured into her by the Holy Ghost, the soul yields herself up, and without any effort, to the impulse of the divine mover. Virtue has become all the more easy to her as she aspires, it would almost seem naturally, to what is most perfect; sacrifices, which used formerly to terrify, now delight her; she makes use of this world as though she used it not, for all true realities, as far as she is concerned, exist beyond this world; in a word, she longs all the more ardently after the eternal possession of the object she loves, as she has been realizing, even in this life, what the apostle describes where he speaks of a creature as being ‘one spirit with the Lord’ by being united to Him in heart.
Such is the result ordinarily produced in the soul by the sweet and healthy influence of the sacred liturgy. But if it seem to us that, although we have followed it in its several seasons, we have not as yet reached the state of detachment and expectation just described, and that the life of Christ has not, so far, absorbed our own individual life into itself, let us be on our guard against discouragement on that account. The cycle of the liturgy with its rays of light and grace for the soul, is not a phenomenon that occurs only once in the heavens of holy Church; it returns each year. Such is the merciful design of God, ‘who hath so loved the world as to give it His only-begotten Son’—of God, ‘who came not to judge the world, but that the world may be saved by Him.’ And holy Church is but carrying out that design by putting within our reach the most powerful of all means for leading man to his God, and uniting him to his sovereign Good; she thus testifies the earnestness of her maternal solicitude. The Christian who has not been led to the term we have been describing by the first half of the cycle will still meet, in this second, with important aids for the expansion of his faith and the growth of his love. The Holy Ghost, who reigns in a special manner over this portion of the year, will not fail to influence his mind and heart; and, when a fresh cycle commences, the work thus begun by grace has a new chance of receiving that completeness which had been retarded by the weakness of human nature.
 Eph. iv. 13.
 St. Matt. vi. 21.
 1 Cor. vii. 31.
 Ibid. vi. 17.
 St. John iii. 16.
 Ibid. 17.