There’s a lot of symbolism behind this wonderful liturgical action. From Praying the Mass: The Prayers of the Priest (pp. 205-209)…
Closely related to the Fraction Rite is the mingling of the Body with the Blood in the chalice. (GIRM 83) The priest quietly says these words:Hæc commíxtio Córporis et Sánguinis Dómini nostri Iesu Christi
** fiat accipiéntibus nobis in vitam ætérnam.**
May this mingling of the Body and Blood … John 6:55; 1 Cor. 10:16
of our Lord Jesus Christ
bring eternal life to us who receive it. … John 6:27,54; Rom. 6:22; 1 John 5:11By these words, the priest prays that the Eucharist might be effective in our lives as the “medicine of immortality,” as it was called by St. Ignatius of Antioch in the early second century. (Catechism 1331, 1405) A simple but profound action accompanies this prayer: the priest takes a small piece of the Host and places it in the chalice, thus mingling the two species of bread and wine.
Although the faithful in the congregation are singing while all this is taking place, everyone should be aware of what is happening and of its great significance. The priest is praying not only for himself but for all who partake of the Body and Blood of our Lord. He is, in effect, praying that we have properly prepared ourselves for Holy Communion; he will pray specifically for himself in a moment.
This mingling has accrued several interpretations over the centuries, seven of which we will consider, each derived from the physical action of uniting the two species of the Eucharist (bread and wine) in the chalice.
The Unity of the Sacrament
The earliest documents that explain the meaning of this union describe it as a declaration that these two species constitute a single whole, that it is one sacrament (Jungmann, The Mass, p. 208), signifying “the unity of the Body and Blood of the Lord in the work of salvation.” (GIRM 83) This point of doctrine has been made by many commentators on the liturgy. Theodore of Mopsuestia explains three times in his liturgical commentary that “although these elements are two, they are nevertheless one in power.” St. Thomas Aquinas addresses the question of “whether the Eucharist is one sacrament or several” in his Summa Theologica, and states that because the Eucharist is the sacrament of the Church’s unity and a sacrament “bears the likeness of the reality of which it is the sacrament,” thus the Eucharist is one sacrament, as the Church is one. He concludes that although “the bread and wine are materially several signs,” the sacrament Itself is “formally and perfectively one.” (Summa Theologiae III, 73, 2) To put it plainly, the Eucharist is not two sacraments, but one sacrament made present under two forms.
This interpretation does not challenge the doctrine of concomitance (which states that the whole Christ is received under the form of bread or under the form of wine). Instead, it confirms this doctrine by physically displaying the inherent unity of the two forms.
A Symbol of the Resurrection
It was only a short theological step from that first meaning to this second one. If the consecrated bread is a sign of the Body of the Lord, and the consecrated wine is a sign of His Blood, and the separate consecration of both was a sign of His death… what event is represented by their union? His Resurrection, of course! This makes the mingling the continuation of the liturgical re-presentation of the Paschal mystery. Having witnessed His Passion and death in the Offertory and Consecration, we now behold His Resurrection. This union is hidden from our view by the chalice, for no one witnessed the very moment of that glorious and ineffable mystery of the Resurrection.
What this means is that the Body that we receive in the Eucharist is the “living and glorious” – that is, resurrected and glorified – “Body of Jesus Christ.” (GIRM 83) His Body is not injured or torn apart when we receive Him in Communion, because glorified bodies enjoy impassibility – from the Latin im- (“not”) and passio (“suffer”), meaning “unable to suffer.” (Summa Theologiae III, 81, 3)
Participation in Christ’s Suffering
Although Christ no longer suffers, He certainly did endure great pains in His Passion. In the Garden of Gethsemane, He asked the Father, “if it be possible, let this chalice pass from me.” (Matt. 26:39; cf. 26:42) The cup is a common Old Testament image symbolizing the wrath of God which is being poured out or drunk. (cf. Ps. 75:8; Isa. 51:17; Jer. 25:15)
Whatever other symbolism the cup in Jesus’ prayer in Gethsemane has, it also represents the great sorrow and suffering that Jesus would bear. To that end, the chalice used at Mass (which contains the Precious Blood that was poured out in the Passion) can be seen as Christ’s “cup of sufferings.” (Douay Catechism, p. 133) Because the mingling (a sign of the Resurrection) takes place in the chalice (a sign of the Passion), the Douay Catechism gives the interpretation that we cannot share in the fruits of the Resurrection unless we are willing to share in His suffering as well, as St. Paul wrote to the Romans. (cf. Rom. 8:17)
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