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March 9, 2018

The Mystery of Faith: Mysterium Fidei

The Mystery of Faith: Mysterium Fidei


About the Mystery of Faith: Mysterium Fidei

The Mystery of Faith is a Eucharistic Acclamation, typically sung, directly after the words of institution transform the bread and wine into the body and blood of Christ during a Roman Rite Catholic Mass. Formerly known as the Memorial Acclamation, the Mysterium Fidei conveys one of the deep truths and mysteries of the faith.

The History of the Mystery

When the liturgists working with Blessed Pope Paul VI came to the Eucharistic Prayer, there were a couple of complicated issues that had to be dealt with in the program of what was called in Italian aggiornamento, the process of moving forward by going back to the original sources. The first was whether or not there should be additional forms of the prayer. It was one of the more popular requests of priests and bishops, since the Roman Canon (what we call Eucharistic Prayer I) was very long and cumbersome, and had one particular view of the Eucharist, which many felt was incomplete. And so, based on a number of ancient prayer forms, the Church now allows for a large number of Eucharistic Prayers.

Within the prayer itself, the Council Fathers discussed at length whether the words of institution – Jesus’ words from the Last Supper should be translated, and whether they should be spoken aloud. It took some time to agree that Jesus did not speak Latin at the Last Supper, and so the sound of the Latin words was not in itself sacred, and of course, since the Apostles were able to record the words of Jesus, he must have said them out loud. But then there was the weird little phrase found towards the end of the institution narrative, in the words over the wine, “Hic est enim calix sanguinis mei, novi et aeterni testamenti: mysterium fidei: qui pro vobis et pro multis effundetur in remissionem peccatorum.” The words mysterium fidei are sort of stuck in the middle of this sentence. They have no scriptural lineage, and were added to the words of Jesus only in the Roman church, sometime around the year 500. So what to do? If the words of institution were to be said aloud, it really made a lot of sense to move forward by going back and letting Jesus speak to us in his own words in this central part of the Eucharist.

The acclamation of the people

But what to do with mysterium fidei? These words, The mystery of faith, are beautiful and remind us of the central truth that at its heart, the Mass is a great mystery of faith. So the experts thought to keep them in some form. Add to that another request, which had been part of the preparatory work for Vatican II. Liturgical scholars looked at the Eucharistic Prayer in many traditions and saw that the people’s participation could be augmented, in particular to affirm the real presence of Jesus in the appearances of bread and wine. Many prayer traditions in the east include an acclamation of the people, a memorial acclamation, at this point in the Mass. These varied from a simple amen after the words over the bread as it becomes the Body of Christ in the Liturgy of Saint James, and in both parts of the consecration in the liturgy of Saint John Chrysostom, to a more extensive acclamation, from the same liturgy: “We show forth your death O Lord, and confess your resurrection.” Among the Coptic Church in Egypt, the Liturgy of Saint Basil is used. Throughout the account of the Last Supper, the faithful acclaim the priest’s words by saying “This is true.” or “Amen.” At the end of the consecration in both of these traditions, the priest recites the words of Saint Paul from 1 Corinthians 11, “Whenever you eat this bread….” And the people make a more extensive response. In Egypt it can be this, “Your death, O Lord, we proclaim. Your holy resurrection and ascension, we confess. We praise you, we bless you, we thank you, O Lord, and we entreat you, O our God.”

The three options in the English translation of the Roman Rite

As a member of the Catholic Church familiar with the current structure of our Eucharistic prayers, you can already see where we are going. The Mysterium Fidei became the invitation to the Memorial Acclamation, and acclamations of Jesus and his great gift to us were borrowed from various traditions. So let’s take a closer look.

The first two are very similar:
1. We proclaim your Death, O Lord and profess your Resurrection until you come again.
2. When we eat this Bread and drink this Cup, we proclaim your Death, O Lord, until you come again.

The text is taken from 1 Corinthians 11:26:
“For as often as you eat this bread and drink the cup, you proclaim the death of the Lord until he comes.”

This acclamation affirms something that we may not often think about – Communion is an act of faith, a proclamation that we believe in the passion of Jesus, and in the second coming. This is especially important. Communion is not the destination of our lives, but rather a proclamation that we know this life is incomplete until Jesus comes to fulfill it. When we look at the Latin we see that it uses slightly different words and so it’s useful to look at that too:

Mortem tuam annuntiamus, Domine, et tuam resurrectionem confitemur, donec venias.

First we note that the Latin is truer to the scriptures, not referring to Jesus coming again – but just to his coming. We might also want to debate about the other verbs; while English and Latin are not mirrors of each other, I like the sense of god-spell of good news that comes from the verb annuntiamus – we announce the Death and Resurrection like a couple announcing their engagement or a news broadcast has an announcer. When it comes to confitemur, the complication comes when most people think of confession as something to do with sins, so profess works just fine. The two vary in that the first makes reference of the resurrection, which is an addition to what we find in the scriptures, while the second is much closer to the scripture passage and refers to eating and drinking, which may make it less appropriate in some circumstances.

The third acclamation is a wonderful conglomeration of sources, it will take a little unpacking. While the English runs:
3. “Save us, Saviour of the world, for by your Cross and Resurrection you have set us free.”

the Latin begins with the title for Jesus, Salvator mundi. Now this is where things get fun. This title for Jesus shows up twice in the scriptures. The first is in the fourth chapter of John’s Gospel, in the story of the Samaritan woman at the well. After the locals have heard from her, and then heard from Jesus himself, they proclaim that they no longer rely on her testimony they know for themselves that Jesus is the Savior of the world. We should put ourselves in the shoes of those Samaritans – we know for ourselves that Jesus is the Savior of the world, and not only that, we ask him to salva nos to save us. The second half of this acclamation should also sound familiar – it is not unlike the dialogue from before each of the Stations of the Cross. “We adore you, O Christ, and we bless you. Because by your holy cross you have redeemed the world.” When we compare the Latin versions of these two prayers the parallel is really strong:

Stations:          quia per sanctam crucem                                       tuam redemisti mundum.

Acclamation: qui   per                     crucem et resurrectionem tuam liberasti   nos.

This third acclamation should clearly be a Lenten favorite, with the link to the Gospel of the Samaritan Woman (Lent 3A) and the link to the Via Crucis. It is really the perfect storm!

Making a choice augments the celebration of the Eucharistic sacrifice

Which brings us, of course to the practical details of what is the value of having three acclamations at this point in the liturgy. To have several choices means that we have to make a choice. Not choosing, or just using the first one all the time because it’s first, well that’s a choice. How much more powerful our liturgical experience of this key moment of the liturgy could be if we assign different acclamations to different seasons of the year, or to special celebrations. I leave that to your creativity.

Glenn CJ Byer
Glenn CJ Byer

Glenn CJ Byer has written widely on the liturgy, including articles on the meaning of the Constitution on the Sacred Liturgy, marriage preparation, the renovation of churches and the anointing of the sick. He speaks widely on the role of lay ministers in the Mass.

This blog series is intended to provide a more in-depth look at the various sung parts of the Mass—their origin, history, current usage, etc. Explore more from this series:


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