Preparation For Pentecost From The Catechism of the Catholic Church [CCC]
Christ Is Always Present. He Disappears From Sight, But Reappears in the Sacraments
(The Mind of Vatican II as Taught in the Catechism of the Catholic Church)
In this age of the Church Christ now lives and acts in and with his Church, in a new way appropriate to this new age. He acts through the sacraments in what the common Tradition of the East and the West calls "the sacramental economy"; this is the communication (or "dispensation") of the fruits of Christ's Paschal mystery in the celebration of the Church's "sacramental" liturgy. (CCC 1076)
The dual dimension of the Christian liturgy as a response of faith and love to the spiritual blessings the Father bestows on us is thus evident. On the one hand, the Church, united with her Lord and "in the Holy Spirit," [Lk 10:21] blesses the Father "for his inexpressible gift [2 Cor 9:15] in her adoration, praise, and thanksgiving.
On the other hand, until the consummation of God's plan, the Church never ceases to present to the Father the offering of his own gifts and to beg him to send the Holy Spirit upon that offering, upon herself, upon the faithful, and upon the whole world, so that through communion in the death and resurrection of Christ the Priest, and by the power of the Spirit, these divine blessings will bring forth the fruits of life "to the praise of his glorious grace." [Eph 1:6] (CCC 1083)
In the liturgy of the Church, it is principally his own Paschal mystery that Christ signifies and makes present. During his earthly life Jesus announced his Paschal mystery by his teaching and anticipated it by his actions. When his Hour comes, he lives out the unique event of history which does not pass away: Jesus dies, is buried, rises from the dead, and is seated at the right hand of the Father "once for all." [8 Rom 6:10; Heb 7:27; 9:12; cf. Jn 13:1; 17:1]
His Paschal mystery is a real event that occurred in our history, but it is unique: all other historical events happen once, and then they pass away, swallowed up in the past. The Paschal mystery of Christ, by contrast, cannot remain only in the past, because by his death he destroyed death, and all that Christ is ‑ all that he did and suffered for all men ‑ participates in the divine eternity, and so transcends all times while being made present in them all. The event of the Cross and Resurrection abides and draws everything toward life. (CCC 1085) The sacraments, and especially the Eucharist, actualize this continuous presence.
"Accordingly, just as Christ was sent by the Father so also he sent the apostles, filled with the Holy Spirit. This he did so that they might preach the Gospel to every creature and proclaim that the Son of God by his death and resurrection had freed us from the power of Satan and from death and brought us into the Kingdom of his Father. But he also willed that the work of salvation which they preached should be set in train through the sacrifice and sacraments, around which the entire liturgical life revolves." [SC 6] (CCC 1086)
Thus the risen Christ, by giving the Holy Spirit to the apostles, entrusted to them his power of sanctifying: [cf. Jn 20:21-23] they became sacramental signs of Christ. By the power of the same Holy Spirit they entrusted this power to their successors. This "apostolic succession" structures the whole liturgical life of the Church and is itself sacramental, handed on by the sacrament of Holy Orders. (CCC 1087)
"To accomplish so great a work" ‑ the dispensation or communication of his work of salvation ‑ "Christ is always present in his Church, especially in her liturgical celebrations.” [SC 7] (CCC 1088)
The Sacraments as efficacious memorials of salvation: they recall and make present our salvation
The Spirit and the Church cooperate to manifest Christ and his work of salvation in the liturgy. Primarily in the Eucharist, and by analogy in the other sacraments, the liturgy is the memorial of the mystery of salvation. (CCC 1099)
That is why the anamnesis (remembrance) is so important. The liturgical celebration always refers to God’s saving interventions in history... In the Liturgy of the Word the Holy Spirit "recalls" to the assembly all that Christ has done for us… the celebration "makes a remembrance" of the marvellous works of God… The Holy Spirit who thus awakens the memory of the Church then inspires thanksgiving and praise (doxology).
Christian liturgy not only recalls the events that saved us but actualizes them, makes them present. The Paschal mystery of Christ is celebrated, not repeated. It is the celebrations that are repeated, and in each celebration there is an outpouring of the Holy Spirit that makes the unique mystery present. (CCC 1104)
The epiclesis ("invocation upon") is the intercession in which the priest begs the Father to send the Holy Spirit, the Sanctifier, so that the offerings may become the body and blood of Christ and that the faithful by receiving them, may themselves become a living offering to God. (CCC 1105)
Together with the anamnesis, the epiclesis is at the heart of each sacramental celebration, most especially of the Eucharist. (CCC 1106)
Liturgy, Sacraments, Faith and Grace
The whole liturgical life of the Church revolves around the Eucharistic sacrifice and the sacraments. [SC 6] (CCC 1113)
The Sacraments of the Church
The sacraments are "of the Church" in the double sense that they are "by her" and "for her." They are "by the Church," for she is the sacrament of Christ's action at work in her through the mission of the Holy Spirit. They are "for the Church" in the sense that "the sacraments make the Church," [St. Augustine, De civ. Dei, 22, 17: PL 41, 779; cf. St. Thomas Aquinas, STh III, 64,2 ad 3] since they manifest and communicate to men, above all in the Eucharist, the mystery of communion with the God who is love, One in three persons. (CCC 1118)
The Sacraments of Faith
"The purpose of the sacraments is to sanctify men, to build up the Body of Christ and, finally, to give worship to God. Because they are signs they also instruct. They not only presuppose faith, but by words and objects they also nourish, strengthen, and express it. That is why they are called 'sacraments of faith.'” [SC 59] (CCC 1123)