Before the wholesale renovation of the Mass after Vatican II, the words were included in the words of Christ: “For this is the Chalice of My Blood, of the new and eternal Covenant: the Mystery of faith: which shall be shed for you and for many unto the remission of sins. As often as ye shall do these things, ye shall do them in remembrance of me.” After the conciliar changes to the liturgy, these words became part of the so-called Memorial Acclamation. The priest strangely said either Let us proclaim the mystery of faith: to which the most popular response of the people was: Christ has died, Christ is risen. Christ will come again. This later became simply: The Mystery of Faith. And the people ended up with several choices for response (none of which is as popular as what was). The celebrant proclaims, as a kind of detached phrase, “The mystery of faith.” And the people may answer with one of three acclamations:
We proclaim your Death, O Lord, and profess your Resurrection, until you come again.
When we eat this Bread and drink this Cup, we proclaim your Death, O Lord, until you come again.
Save us, Savior of the world, for by your Cross and Resurrection you have set us free.
They say imitation is the sincerest form of flattery and the liturgical innovations certainly borrowed from the East in pursuit of what they thought were earlier and purer forms of the rite. Whatever. I am not sure there is a neat paper trail to where and how and when this phrase became part of the Western rite. In any case, however, wherever it is placed, it is still a nice phrase. From a November 29, 1202, letter of Pope Innocent III we read:
‘Mystery of faith’ is used, because here what is believed differs from what is seen, and what is seen differs from what is believed. For what is seen is the appearance of bread and wine, and what is believed is the reality of the flesh and blood of Christ and the power of unity and love.It is actually a very concise and clear statement of the hidden mystery that is not apparent to the eye but known and held by faith. While this is certainly true of the Real Presence, seen by the eye as bread and wine (as well as the nose and mouth), faith affirms that it is the Body and Blood of Christ. It could also refer to baptismal water which is not just water but water with God's Word, doing what that Word says. But who is to say that the mystery of faith is not also the most central mystery -- the Holy Trinity! In any case, I like the phrase and wish that we used it more and tried to explain things away less. By the way, I am also rather fond of the acclamation itself (though others have complained about whether it ever fit where it had been): Christ has died. Christ is risen. Christ will come again. It need not be in the Eucharistic Prayer but it could be placed somewhere as more fitting words that seem destined to come out of ICEL and liturgical reform committees today. Lastly, there is something to be said about the Benedictus (as it was in the EF) as a profound acclamation. Blessed is He who comes in the Name of the Lord! Amen.
So now you know the kind of random thoughts that flow through my crooked thought passages on a Friday (my day off)....