In the Roman Mass a ceremony which forms part of the Fraction Rite, in which the celebrant breaks the consecrated bread and drops a broken particle into the chalice, saying: "Haec commixtio Corporis et Sanguinis Domini nostri Iesu Christi fiat accipientibus nobis in vitam aeternam" ("May this commingling of the body and blood of our Lord Jesus Christ bring eternal life to us who receive it").
It is remarkable that the same ceremony is found in some form among all the liturgies of East and West. This fact indicates that it was a generally accepted practice in Christian antiquity before the Church became divided. Actually, it started in Syria and quickly became the property of the universal Church.
Unfortunately the theological significance of this rite was lost sight of in the course of time. According to Syrian documents, the Commingling is the connecting link between Sacrifice and Communion. Commingling, with the Consignation as its initial act, symbolizes that the sacrificial chalice has been accepted by the Father and returned to the participants at Mass as "spiritualized," i.e., filled with the Spirit of God ("May… avail us unto eternal life").
Our earthly gifts are returned to us as heavenly food. Whereas the double consecration of bread and wine is the twofold sign of Christ's Body and Blood, the Commingling symbolizes the union of the two Species and therefore the glorified humanity of the risen Christ, laden with gifts that lead humanity to a participation in Christ's divinity and immortality. In this symbolic sequence of ceremonial, the Commingling was intended to express the sacramental effect of Communion. Commingling, then, symbolizes the transfiguring Resurrection of Christ, his humanity's being taken up by the Spirit of God, thereby able to fill the human race with the same Spirit. Hence, this rite of Commingling was meant to be a visual representation of what was verbally expressed in the epicle sis, namely, that God's Spirit descends upon the elements and transforms them into the life-giving Christ. Both epiclesis and Commingling are situated on the symbolic level, pointing to and unfolding the same reality of the Eucharist as Sacrament of humanity's spiritual transfiguration through eating and drinking Christ's glorified Body and Blood.
Bibliography: j. p. de jong "Le Rite de la commixtion de la messe romaine dans ses rapports avec les liturgies syriennes," Archiv für Musikwissenschaft 4.2 (1956) 245–278; 5.1 (1957) 33–79. j. a. jungmann, The Mass of the Roman Rite, tr. f. a. brunner (rev. ed. New York 1959) 475–479.
[j. p. de jong/eds.]