12/11/2023
https://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_const_19631204_sacrosanctum-concilium_en.html
Par. 2: "For the liturgy, 'through which the work of our redemption is accomplished,' most of all in the divine sacrifice of the Eucharist, is the outstanding means whereby the faithful may express in their lives, and manifest to others, the mystery of Christ and the real nature of the true Church."
Par 7: "Christ is always present in His Church, especially in her liturgical celebrations. He is present in the sacrifice of the Mass, not only in the person of His minister, 'the same now offering, through the ministry of priests, who formerly offered himself on the cross', but especially under the Eucharistic species. By His power He is present in the sacraments, so that when a man baptizes it is really Christ Himself who baptizes. He is present in His word, since it is He Himself who speaks when the holy scriptures are read in the Church. He is present, lastly, when the Church prays and sings, for He promised: 'Where two or three are gathered together in my name, there am I in the midst of them' (Matt. 18:20).
Christ indeed always associates the Church with Himself in this great work wherein God is perfectly glorified and men are sanctified. The Church is His beloved Bride who calls to her Lord, and through Him offers worship to the Eternal Father.
Rightly, then, the liturgy is considered as an exercise of the priestly office of Jesus Christ. In the liturgy the sanctification of the man is signified by signs perceptible to the senses, and is effected in a way which corresponds with each of these signs; in the liturgy the whole public worship is performed by the Mystical Body of Jesus Christ, that is, by the Head and His members.
From this it follows that every liturgical celebration, because it is an action of Christ the priest and of His Body which is the Church, is a sacred action surpassing all others; no other action of the Church can equal its efficacy by the same title and to the same degree."
Par 8: "In the earthly liturgy we take part in a foretaste of that heavenly liturgy which is celebrated in the holy city of Jerusalem toward which we journey as pilgrims."
Par 10: "Nevertheless the liturgy is the summit toward which the activity of the Church is directed; at the same time it is the font from which all her power flows. For the aim and object of apostolic works is that all who are made sons of God by faith and baptism should come together to praise God in the midst of His Church, to take part in the sacrifice, and to eat the Lord's supper.
The liturgy in its turn moves the faithful, filled with 'the paschal sacraments,' to be 'one in holiness'; it prays that 'they may hold fast in their lives to what they have grasped by their faith'; the renewal in the Eucharist of the covenant between the Lord and man draws the faithful into the compelling love of Christ and sets them on fire. From the liturgy, therefore, and especially from the Eucharist, as from a font, grace is poured forth upon us; and the sanctification of men in Christ and the glorification of God, to which all other activities of the Church are directed as toward their end, is achieved in the most efficacious possible way."
Lumen Gentium par. 11: "Taking part in the Eucharistic sacrifice, which is the Source and Summit of the whole Christian life, they offer the Divine Victim to God, and offer themselves along with It."