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A Step-by-Step Theological Explanation of the Roman Missal

Updated: Jun 29, 2023

By Dom Dalmasso

Before commencing a pedagogical and catechetical walk-through of the Roman Missal, an important preliminary theological observation is in order. The Mass is not a mere commemoration where a local community expresses its own meaning in order to experience social solidarity; rather, the Mass is the making present, here and now, of Christ’s one eternal sacrifice that is offered by the Son and accepted by the Father, and that is effective through the Spirit in impressing its meaning on us. This meaning actively realizes the essential solidarity which the “body of Christ” constitutes. In other words, although the Church, through her sacramental ministry, confects the Eucharist, we also see here that the Eucharist, in fact, brings the Church into being. The Mass, therefore, is the “becoming one flesh” of the bridegroom with the bride: this is the source of our new life and its goal, i.e., communion with God. This theological backdrop is present from the beginning in the Church’s consciousness, as we see in the writings of the Didache, Saint Ignatius of Antioch, Saint Justin Martyr, Saint Irenaeus, and many others. But we especially see it in the New Testament, where Saint Paul tells us, “The cup of blessing that we bless, is it not a sharing in the blood of Christ? The bread that we break, is it not a sharing in the body of Christ? Because there is one bread, we who are many are one body, for we all partake of the one bread” (1 Cor 10:16-17, NRSV).

The Mass is constituted of two distinct but inseparable movements: the liturgy of the Word and the liturgy of the Eucharist. In fact, the general pattern of the Christian liturgy is discernable in the overarching structure of the book of Revelation: Chapter 1 offers an introduction, opening with the description of a lector and an assembly, chapters 2 through 13 revolve around an image of the scroll (there are addresses to the churches throughout the world as well as descriptions of the various seals and the central biblical story of the scroll), chapters 14 through 19 revolve around an image of the lamb and his victory, chapter 20 speaks of the realized eschatology that the pilgrim Church lives in, and chapters 21 through the first half of 22 speak of the fulfillment of all things. The book ends, in the second half of chapter 22 with a closing blessing and the exclamation found in the Didache (an early description of the Apostolic Church’s liturgy) Maranatha (Come, Lord Jesus!).

The introductory phase of the liturgy is constituted of the Entrance, the Greeting, the Penitential Act, the Kyrie, the Gloria, and the Collect. These serve as an opening to the liturgical event as a whole. The Entrance (Introit) is a thematic hymn (commonly taken from the Psalter) sung by the choir as the priest and the altar servers process into the sanctuary and take their place in it. The Greeting of the priest to the assembly solidifies both the representative nature of the minister (Dóminus vobiscum) and the intentional presence of the assembly in their active participation in his “spirit” (et cum spiritu tuo). The Penitential Act (Confiteor) and the Kyrie (Kyrie eleison, Christe eleison, Kyrie eleison) are the ways in which the assembly, led by the minister, confess their sins and ask the Blessed Trinity for mercy. Then follows the Gloria in excelsis Deo, a hymn most likely dating back to the second century,[1] which, like the Kyrie, is structured in a threefold pattern of praise to each person of the Trinity. The Collect concludes this introductory movement by the priest gathering the attention of the assembly (oremus) and invoking the Father, through the Son in union with the Spirit, on behalf of all. Historically, the Collect was an introductory prayer said at an assembly point other than where the Mass was celebrated (ad collectam versus ad missam).[2]

Then follows the Lesson (from the Old Testament), the Epistle (from the New Testament letters), and the Gospel reading (from Matthew, Mark, Luke, or John). The Gradual (often called the Responsorial Psalm) and the Alleluia (sung with a verse) break up these three readings. Pope Benedict explains, in Sacramentum Caritatis, that:

If it is to be properly understood, the word of God must be listened to and accepted in a spirit of communion with the Church and with a clear awareness of its unity with the sacrament of the Eucharist. Indeed, the word which we proclaim and accept is the Word made flesh (cf. Jn 1:14); it is inseparably linked to Christ's person and the sacramental mode of his continued presence in our midst.[3]

This goes back to the observation made earlier that the liturgy of the Word and the liturgy of the Eucharist, although distinct, are inseparable.

After reading from the Sacred Scriptures, the priest gives a homily. The Church’s latest constitution on the liturgy, from the Second Vatican Council, explains that “by means of the homily the mysteries of the faith and the guiding principles of the Christian life are expounded from the sacred text, during the course of the liturgical year; the homily, therefore, is to be highly esteemed as part of the liturgy itself.”[4]

In the early Church, it was at this juncture that the Catechumens (new converts seeking baptism) were dismissed, and the assembly of the baptized, led as usual by the minister, would enter into the movement of the liturgy of the Eucharist. To be part of the New Covenant one had to swear an oath of allegiance (pistis) to Christ and be baptized; as the Scriptures put it, “believe in Christ and be baptized.”[5] Now, the Catechism of the Catholic Church calls baptism “the sacrament of faith”[6] (sacramentum being Latin for “oath”), thereby identifying baptism as an “oath of allegiance.” This explains the placement of the Creed, which is the recitation of the profession of faith of the local church (and of course of the universal Church).

The Creed is followed by a series of petitions with which the assembly turns to the Father in the name of the Son. They are usually as follows: (1) For the needs of the Church, (2) for public authorities and the salvation of the whole world, (3) for those burdened by any kind of difficulty, and (4) for the local community.[7]

The Offertory is the movement which prepares the gifts of bread and wine for the Eucharistic prayer. The corporal (a square cloth upon which the chalice is placed), the purificator (a sacred napkin), the pall (stiffened linen used to cover the chalice), the missal, the paten (a sacred dish in which the host of bread is placed), and the chalice are placed on the altar, and the elements of bread and wine are brought to the priest (the Offertory hymn is sung during this period). Pope Benedict comments that “in the bread and wine that we bring to the altar, all creation is taken up by Christ the Redeemer to be transformed and presented to the Father. In this way we also bring to the altar all the pain and suffering of the world.”[8] The priest then elevates the paten with the host giving thanks and anticipating the coming presence of the Lord. Then, at the side of the altar, he mixes a drop of water in the chalice, praying that our humanity may share in Christ’s divinity. Just as with the bread, he elevates the chalice with the wine and the water, giving thanks and anticipating the coming presence of the Lord. He finishes by incensing the gifts, the altar, and the cross, and moves to the side of the altar to wash his hands, praying for purification.

Then begins the Eucharistic prayer (called the anaphora) which is comprised of (1) the thanksgiving (also known as the Preface: a prayer recited aloud by the priest after asking the assembly to lift up their hearts and to turn toward the Father in thanksgiving and justice), (2) the acclamation (where the assembly sings the Sanctus), (3) the epiclesis (where the Holy Spirit is invoked so that through his power the elements may become the body, blood, soul, and divinity of Jesus Christ), (4) the institution narrative and Consecration (where the words and actions of Our Lord are spoken and performed by the priest: Hoc est enim corpus meum, and Hic est enim calix sanguinis mei), (5) the anamnesis (where the Church celebrates the memorial of the Lord’s passion, resurrection, and ascension), (6) the oblation (where the Church offers the unblemished sacrificial Victim in the Holy Spirit to the Father), (7) the intercessions (where the Church offers the oblation for the entire cosmic Church), and (8) the concluding doxology (where the priest exclaims: Per ipsum et cum ipso et in ipso est tibi Deo Patri omnipotenti, in unitate Spiritus Sancti, omnis honor et gloria, per omnia sæcula sæculorum; and the assembly responds: Amen). Pope Benedict points out the crucial relationship of the epiclesis (the power of the Holy Spirit) with the words of consecration (the power of the Word of God) in the anaphora: “Eucharistic spirituality and theological reflection are enriched if we contemplate in the anaphora the profound unity between the invocation of the Holy Spirit and the institution narrative.”[9]

After the Eucharistic prayer begins the communion rite, where the priest leads the assembly in the Lord’s prayer (the Pater Noster) and concludes with a petition for protection and peace in this time of anticipation of the Lord’s second coming. It is here that the priest exclaims to the people: Pax Domini sit semper vobiscum, to which they respond: Et cum spiritu tuo. And the faithful exchange the sign of peace by bowing or shaking the hand of the member to their immediate left and right. Pope Benedict offers two observations on the sign of peace, one practical and the other theological: “Nothing is lost when the sign of peace is marked by a sobriety which preserves the proper spirit of the celebration, as, for example, when it is restricted to one's immediate neighbours,”[10] and, “by its nature the Eucharist is the sacrament of peace. At Mass this dimension of the eucharistic mystery finds specific expression in the sign of peace.”[11]

The priest proceeds to drop a fragment of the consecrated host in the chalice and prays the following: Hæc commíxtio Córporis et Sánguinis Dómini nostri Iesu Christi at accipiéntibus nobis in vitam ætérnam. The assembly then proceeds to sing the Agnus Dei, after which the priest turns toward the people and presents a host for them to see, saying: Ecce Agnus Dei, ecce qui tollit peccáta mundi. Beáti qui ad cenam Agni vocáti sunt, and the assembly responds: Dómine, non sum dignus, ut intres sub tectum meum, sed tantum dic verbo et sanábitur ánima mea. The priest consumes the host and drinks the chalice. The faithful approach the altar in an orderly fashion and receive, for consumption, the Eucharistic elements as the priest says, respectively: Corpus Christi and Sanguis Christi, and the recipient responds: Amen.

Once all the faithful have regained their place, and once the priest has purified the ciboriums (where many consecrated hosts are kept for distribution), the patten, and the chalice(s), the concluding part of the mass takes place. The priest greets the people: Dóminus vobiscum, to which they respond: Et cum spiritu tuo, and then gathers their attention (oremus) and prays the Post Communion prayer. He then blesses the assembly.

The Mass concludes with the priest saying Ite, missa est to the people (they respond Deo Gratias). Pope Benedict remarks on the meaning of this dismissal: “These words help us to grasp the relationship between the Mass just celebrated and the mission of Christians in the world. […] The word ‘dismissal’ has come to imply a ‘mission.’ These few words succinctly express the missionary nature of the Church.”[12] The priest and the altar boys process out and return to the sacristy.

In conclusion, the Mass is the ritual “entering-into” the one and eternal sacrifice of the Lord whereby we encounter Word and Sacrament in a way which transforms us, and which constitutes us as members of the Body of Christ. In the Mass we participate in Jesus Christ’s sacrifice to the Father, which is accepted by him (in his resurrection and ascension), and we receive the effects of this sacrifice through the work of the Holy Spirit in our persons. Thus, the Paschal mystery, which holds together the death, resurrection, and ascension of Our Lord Jesus Christ, is the one source of our redemption and anticipated glorification.

__________________________________________________________________________________ [1] Adrian Fortescue, The Mass: A Study of the Roman Liturgy (Fitzwilliam, New Hampshire: Loreto Publications, 2003), 241. [2] Fortescue, The Mass, 245. [3] Post-Synodal Apostolic Exhortation Sacramentum Caritatis of the Holy Father Benedict XVI, to the Bishops, Clergy, Consecrated Persons and the Lay Faithful on the Eucharist as the Source and Summit of the Church’s Life and Mission (22 February 2007), §45. [4] Second Vatican Council, Constitution on the Sacred Liturgy Sacrosanctum Concilium (4 December 1963), §52. [5] See: Mk 16:16, Acts 2:38, Acts 22:16. [6] Catechism of the Catholic Church (United States Catholic Conference, Inc., 1994), 1236. [7] The General Instructions of the Roman Missal (Vaticana, Vatican City State: Libreria Editrice, 2008), 28. [8] Pope Benedict XVI, Sacramentum Caritatis, §47. [9] Pope Benedict XVI, Sacramentum Caritatis, §48. [10] Pope Benedict XVI, Sacramentum Caritatis, §49. [11] Pope Benedict XVI, Sacramentum Caritatis, §49. [12] Pope Benedict XVI, Sacramentum Caritatis, §51.

Dom Dalmasso is a 2023 graduate from Holy Apostles College and Seminary with a Bachelor of Arts in Theology and philosophy. He was a Benedictine monk from early 2011 to late 2012 at Our Lady of Clear Creek Abbey in Oklahoma and was an active-duty United States Marine from August 2014 to August 2018. He runs the YouTube Show / Podcast The Logos Project, and is the editor-in-chief of The Ecclesia Blog. He is currently pursuing a Master of Arts in Dogmatic Theology at Holy Apostles.

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