Catholic Glossary

Agnus Dei

also: Lamb of God

The Agnus Dei ('Lamb of God who takes away the sins of the world, have mercy on us… grant us peace') is the Church's prayer during the Fraction, calling on Christ by the title given Him by John the Baptist (John 1:29). It identifies the Victim on the altar as the true Passover Lamb, whose blood rescues the new Israel from sin and death.

Ambo

The Ambo is the dignified place in the sanctuary reserved for the proclamation of Sacred Scripture. The Scripture readings, the Responsorial Psalm, and the Exsultet (at the Easter Vigil) are given from the ambo. Because of the dignity of the Word of God, the ambo should be distinguished from any other place used for announcements or commentary.

Amen

'Amen' is a Hebrew word of affirmation that Christians inherited from Jewish worship. It means 'so be it,' 'truly,' or 'it is firm.' It is the people's way of making a prayer their own. The 'Great Amen' at the end of the Eucharistic Prayer is especially important — it ratifies everything the priest has prayed in the name of the whole Church. Jesus Himself is called 'the Amen' in Revelation 3:14.

Anamnesis

Anamnesis (Greek: 'remembrance') is not merely recollection but a sacred memorial that makes present what it recalls. At the Lord's command — 'Do this in memory of me' — the Church in the Eucharist does not just remember Calvary; it makes Christ's one, once-for-all sacrifice truly present on the altar. The anamnesis proper is the part of the Eucharistic Prayer immediately after the consecration, where the Church recalls the Paschal Mystery (Passion, Resurrection, and Ascension) and offers the Victim to the Father.

Chalice

The Chalice is the cup used at Mass to hold the wine that will become, through transubstantiation, the Blood of Christ. It should be made of precious material (traditionally gold or silver) and, per the Church's norms, its interior should be gilded. The chalice is one of the sacred vessels, consecrated by a bishop before liturgical use.

Collect

The Collect (pronounced KAH-lekt; from Latin collecta, 'gathering') is the Church's opening prayer at Mass. After 'Let us pray,' a brief silence is kept so the faithful can bring their intentions to mind; the priest then gathers them all into a single prayer addressed to the Father through Christ in the Holy Spirit. It expresses the character of the day or feast.

Commingling

After the Fraction, the priest drops a small piece of the consecrated Host into the Chalice, praying quietly, 'May this mingling of the Body and Blood of our Lord Jesus Christ bring eternal life to us who receive it.' The gesture signifies the reunion of the Body and Blood of the risen Christ, who is not divided in the Eucharist but wholly present under each species.

Concomitance

The doctrine of Concomitance teaches that although the consecrated bread is substantially the Body of Christ and the consecrated wine substantially His Blood, the risen Christ is indivisible — so His Body, Blood, Soul, and Divinity are all present under each species. This is why a communicant who receives only the Host, or only from the chalice, still receives the whole Christ. It also undergirds the reverence due to even the smallest particle of either species.

Consecration

The Consecration is the heart of every Mass. Within the Eucharistic Prayer, the priest repeats the very words Jesus used at the Last Supper: 'Take this, all of you, and eat of it, for this is my Body…' and over the chalice, 'This is the chalice of my Blood…' At these words, empowered by the Holy Spirit (see Epiclesis), transubstantiation takes place. The priest genuflects in adoration after each consecration. This is the supreme action of Christian worship — the sacrifice of Calvary made present.

Consubstantial

Consubstantial (Latin: consubstantialis; Greek: homoousios) was the word chosen by the First Council of Nicaea (325) to confess that the Son is of the same divine substance as the Father — equally God, eternally begotten, not made. In the English Mass, we say 'consubstantial with the Father' in the Nicene Creed. The earlier translation 'one in Being with the Father' conveyed the same meaning but less technically. This single word carries the weight of the fourth-century battle against Arianism, which had denied Christ's full divinity.

Creed

also: Nicene Creed, Apostles' Creed, Symbol of Faith

A Creed (Latin credo, 'I believe') is a concise profession of Christian belief. The Nicene-Constantinopolitan Creed, composed by the first two ecumenical councils (325, 381), is the Church's fullest liturgical profession and is prayed at Mass on Sundays and solemnities. The Apostles' Creed — an older baptismal formula — may be used, especially during Lent and Easter Time.

Deposit of Faith

The Deposit of Faith is the whole of divine revelation — the Word of God — entrusted by Christ to His Apostles and handed down in the Church through Sacred Scripture and Sacred Tradition. Public revelation concluded with the death of the last Apostle; the Church does not add to the Deposit, but the understanding of it grows under the guidance of the Holy Spirit through the work of theologians, saints, and the Magisterium.

Doxology

A doxology (Greek: doxologia, 'word of glory') is a brief hymn of praise to the Trinity. The 'Glory Be' is the most common example. The Eucharistic Prayer ends with the Great Doxology — 'Through him, and with him, and in him, O God, almighty Father, in the unity of the Holy Spirit, all glory and honor is yours, for ever and ever' — to which the people respond with the Great Amen, the climactic affirmation of the whole prayer.

Epiclesis

The Epiclesis (Greek: 'invocation upon') is the moment in the Eucharistic Prayer when the priest explicitly calls upon the Holy Spirit to consecrate the gifts of bread and wine. In Eucharistic Prayer II, for example: 'Make holy, therefore, these gifts, we pray, by sending down your Spirit upon them like the dewfall…' A second epiclesis follows the consecration, asking that those who receive Communion may be gathered into one by the Holy Spirit. The Eastern Churches place especially strong emphasis on the epiclesis as the moment of consecration.

Eucharist

also: Blessed Sacrament, Holy Eucharist

The Eucharist (from the Greek eucharistia, 'thanksgiving') is the sacrament instituted by Christ at the Last Supper in which He gives Himself — Body, Blood, Soul, and Divinity — under the signs of bread and wine, to be both the sacrifice of the New Covenant and the food of Christian pilgrims. The Second Vatican Council called the Eucharist 'the source and summit of the Christian life' (LG §11). It is sacrifice (Calvary made present), presence (Christ truly there), and communion (our union with Him and one another).

Eucharistic Prayer

also: Canon, Anaphora

The Eucharistic Prayer (also called the Anaphora in Eastern rites, or historically the 'Canon' when referring to the Roman Canon / Eucharistic Prayer I) is the central prayer of the Mass. Its structure includes: (1) Thanksgiving in the Preface, (2) the Sanctus, (3) the Epiclesis invoking the Holy Spirit, (4) the Institution Narrative and Consecration, (5) the Anamnesis (memorial), (6) the Oblation (offering), (7) Intercessions for the living and dead, and (8) the Final Doxology and Great Amen. In the current Roman Missal, the priest may use any of ten approved Eucharistic Prayers.

Ex Opere Operato

Ex opere operato (literally 'from the work worked') is the Latin phrase that expresses the Catholic doctrine that the sacraments, when validly celebrated, confer the grace they signify through Christ's own action — not through the holiness of the priest or the fervor of the recipient. This does not mean the recipient's disposition is irrelevant: while the sacrament is effected regardless of the minister's state, the fruit the recipient receives depends on their openness to grace. A priest in mortal sin still confects a valid Eucharist; an unworthy communicant commits sacrilege rather than gaining grace.

Feast

A Feast is a day of the second liturgical rank, below solemnities. Feasts of the Lord (like the Transfiguration and Presentation) take precedence over Sundays in Ordinary Time; other feasts do not. The Gloria is sung at feasts but the Creed is not.

Fraction

The Fraction is the ancient ritual of breaking the consecrated Host, echoing what Jesus did at the Last Supper. In early Christian usage, the Eucharist was known as 'the breaking of bread' (Acts 2:42). The gesture signifies that the many faithful are made one by partaking of the one Bread of Life. The Agnus Dei is sung during the Fraction.

Holy Communion

Holy Communion is the sacramental reception of the Body and Blood of Christ under the species of bread and wine. To receive worthily, a Catholic must be in a state of grace (free from mortal sin), have fasted for one hour beforehand, and believe what the Church teaches about the Real Presence. Those not in full communion with the Catholic Church are ordinarily not to receive; they may approach with arms crossed for a blessing. Daily reception, when properly disposed, is encouraged by the Church.

Homily

The Homily is an integral part of the Mass in which an ordained minister (bishop, priest, or deacon) — never a lay person — expounds the Scripture readings or another liturgical text of the day. It is required on Sundays and Holy Days of Obligation and commended on weekdays. Its purpose is to nourish the Christian life of the faithful from God's Word.

Hypostatic Union

The Hypostatic Union is the theological term for the unique way in which the Son of God is both true God and true man — one divine Person subsisting in two complete natures, divine and human, without confusion, change, division, or separation. This dogma was defined at the Council of Chalcedon in 451 in response to heresies that either denied the full divinity of Christ (Arianism, Nestorianism) or merged His two natures (Monophysitism). The Incarnation makes possible every grace of the Christian life: because Christ is truly man, He can suffer for us; because He is truly God, His sacrifice has infinite worth.

Incarnation

The Incarnation (Latin incarnatio, 'enfleshment') is the mystery that the eternal Son of God, without ceasing to be God, took on a complete human nature in the womb of the Virgin Mary by the power of the Holy Spirit. Jesus Christ is thus true God and true man in one divine Person — the Hypostatic Union. The Creed teaches us to bow at the words 'and by the Holy Spirit was incarnate of the Virgin Mary, and became man.'

Introductory Rites

The Introductory Rites of the Mass comprise the Entrance Chant, Sign of the Cross and Greeting, Penitential Act, Kyrie, Gloria, and Collect. Their purpose, per the GIRM, is 'that the faithful, coming together, establish communion and dispose themselves properly to listen to the Word of God and to celebrate the Eucharist worthily.'

Liturgy of the Eucharist

The Liturgy of the Eucharist is the sacrificial and sacramental heart of the Mass. It begins with the Preparation of the Gifts, continues through the Eucharistic Prayer with its consecration, and culminates in Holy Communion. Here Christ becomes truly present, is offered to the Father, and is received as food for the life of the world.

Liturgy of the Word

The Liturgy of the Word is the portion of the Mass in which God speaks to His people through Sacred Scripture, and the Church responds in faith. It includes the biblical readings, the Responsorial Psalm, the Gospel Acclamation and Gospel, the Homily, the Profession of Faith (Creed), and the Universal Prayer. Christ is truly present in His Word, which is proclaimed and explained so the faithful may be nourished by it.

Magisterium

The Magisterium (from Latin magister, 'teacher') is the authoritative teaching office of the Catholic Church. It is exercised by the Pope and by the bishops in communion with him. Its mission is to guard and hand on the Deposit of Faith entrusted to the Apostles. When it teaches definitively on matters of faith or morals, it does so with Christ's own authority, preserved from error by the Holy Spirit.

Memorial

A Memorial is the lowest rank of liturgical day with its own Mass (after solemnities and feasts). Obligatory memorials must be observed; optional memorials may be celebrated or omitted at the priest's discretion in favor of the ferial (weekday) Mass of the current liturgical season.

Monstrance

The Monstrance (from Latin monstrare, 'to show') is the ornate vessel, usually with a glass center surrounded by rays, used to display the consecrated Host for Eucharistic adoration and Benediction. It makes visible the Real Presence to the worshipping faithful and is one of the most treasured sacred objects of the Catholic patrimony.

Oblation

Oblation is the act of offering. In the Mass, the Church, in union with Christ the High Priest, offers the Victim just made present on the altar — Christ Himself — to the Father. This offering (often explicit in the Eucharistic Prayer immediately after the Anamnesis) is the Church's participation in Christ's own self-offering. The faithful are also called to offer themselves along with Christ, joining their sufferings and lives to His.

Paschal Mystery

The Paschal Mystery is the one act of Christ's Passover (Latin: pascha) from death to life — His suffering, crucifixion, resurrection, and ascension — by which He redeemed the human race. Every Mass celebrates and makes this mystery really present; every sacrament draws its power from it. The whole liturgical year, especially the Triduum, leads the Church into deeper participation in this mystery. 'Paschal' means 'of Passover' — Christ is the new Passover Lamb whose blood delivers us from sin and death.

Paten

The Paten is the small, shallow plate — usually matching the chalice — on which the principal Host is placed during the Eucharistic Prayer and from which Communion is often distributed. Like the chalice, it is a sacred vessel made of precious material and consecrated for liturgical use.

Preface

The Preface opens the Eucharistic Prayer. After the dialogue ('The Lord be with you… Lift up your hearts… Let us give thanks to the Lord our God'), the priest gives thanks to the Father for His works of salvation in terms proper to the season or feast. The Preface concludes by joining the earthly liturgy to the heavenly one in the Sanctus.

Real Presence

The Real Presence means that Jesus Christ is present in the Eucharist not merely symbolically or spiritually, but truly, really, and substantially. This presence includes the whole Christ — His Body and Blood, together with His Soul and Divinity — under each of the Eucharistic species. It is not a figure of speech: what was bread and wine has become, through transubstantiation, the very Person of the risen Lord. This doctrine is the heart of Catholic Eucharistic faith and the basis of every traditional practice of Eucharistic adoration, genuflection before the tabernacle, and reverence during Mass.

Sacramental

A sacramental is a sacred sign that resembles the sacraments — such as a blessing, holy water, the Sign of the Cross, a rosary, or a scapular — but is instituted by the Church rather than by Christ directly. Sacramentals do not confer grace ex opere operato as the sacraments do; rather, they prepare us to receive grace and dispose us to cooperate with it. Every sacramental is ultimately rooted in the Paschal Mystery.

Sacrifice of the Mass

The Mass is not a new sacrifice distinct from Calvary, nor merely a symbolic remembrance. It is the one sacrifice of Christ on the Cross made truly present, in an unbloody manner, on the altar. The Victim is the same (Christ); the Priest is the same (Christ, acting through the ordained priest); only the manner differs. Because it is Christ's own sacrifice, the Mass has infinite value. The Council of Trent defined this doctrine against Reformers who denied the sacrificial character of the Mass.

Sanctoral Cycle

also: sanctoral

The Sanctoral Cycle (Latin: sanctorale) is the portion of the Church's calendar consisting of fixed feasts of the saints — e.g., St. Joseph on March 19, the Immaculate Conception on December 8. It runs parallel to the Temporal Cycle, which celebrates the mysteries of Christ (Advent, Christmas, Lent, Easter, Pentecost, Ordinary Time) and is largely moveable based on Easter.

Sanctuary

The Sanctuary (from Latin sanctuarium, 'holy place') is the part of the church set apart for the altar and the liturgical action of the clergy and ministers. Traditionally separated from the nave by an altar rail or a step, the sanctuary signifies the holiness of the action performed there and the distinction between the ministerial priesthood and the baptismal priesthood of the faithful.

Sanctus

also: Holy, Holy, Holy

The Sanctus unites the faithful on earth with the worship of the angels in heaven. Its text combines the vision of the seraphim in Isaiah 6:3 with the crowds' cry as Jesus entered Jerusalem (Matthew 21:9). On the threshold of the Eucharistic consecration, the Church sings the song the angels sing without ceasing before the throne of God.

Solemnity

A Solemnity is the highest rank of liturgical day, celebrating the greatest mysteries of faith or the most important saints. Solemnities always include the Gloria and Creed, have proper readings, and begin liturgically with First Vespers the evening before. Examples include Christmas, Easter, Pentecost, the Assumption, All Saints, and the Immaculate Conception.

Species

also: Eucharistic species, sacred species

In Eucharistic theology, 'species' refers to the visible, tangible appearances of bread and wine — their color, shape, taste, texture. After consecration, these appearances remain unchanged, but the underlying substance is no longer bread and wine but the Body and Blood of Christ. Christ is wholly present under each species and in every particle; this is why even the smallest fragment is treated with reverence and why the Precious Blood must never be spilled.

Tabernacle

The Tabernacle is the locked box — traditionally of precious materials — in which the consecrated Hosts are kept after Mass for Communion to the sick and for adoration. A sanctuary lamp burns nearby to indicate Christ's presence. The word comes from the Latin for 'tent,' recalling the tent of meeting where God dwelt among His people in the Old Testament.

Transubstantiation

also: transubstantiate, transubstantiated

Transubstantiation is the Church's technical term for what happens at the consecration of the Mass. By the power of Christ's words and the invocation of the Holy Spirit, the entire substance of the bread is changed into the substance of the Body of Christ, and the entire substance of the wine into the substance of His Blood. The outward appearances (Latin: species) — what we see, taste, touch — remain unchanged, but the underlying reality is wholly different. The Council of Trent defined this teaching dogmatically in 1551, following the theological vocabulary developed especially by St. Thomas Aquinas. It is called a 'substantial' change precisely because it reaches the very being of the thing, not merely its accidents.