The eucharistic prayer offers a theologically rich indication of the ordained minister’s engagement of the priesthood of the faithful. While it is true that the priest recites the words of institution in the first person and recites the anaphora by himself, aside from the words of institution, the anaphora is in the first person plural. Thus the priest is speaking it in the name of the rest of the assembly. Hervé Legrand’s analysis of the liturgical vocabulary of the first millennium shows in the Roman sacramentaries the subject of the verb “celebrate” is always the “we” of the assembly, never the “I” of the priest. The liturgical “we” made Lombard say that a priest cut off from the Church could not validly celebrate Mass since he could not say offerimus quasi ex persona Ecclesiae in the anamnesis.
This liturgical “we” is further emphasized in the dialogue between priest and people in the liturgy. For example, in the exchange, “The Lord be with you,” and the response, “And with your spirit,” there is a reciprocal recognition of the Lord’s presence in both the assembly and in the minister. St. John Chrysostom commented that the eucharistic prayer is a common prayer because the priest does not give thanks (which is to say that he does not celebrate the Eucharist, the “thanksgiving”) alone but only with the people. He does not begin the eucharistic prayer without first gathering the faithful and assuring their agreement to enter into this action through the dialogue: “Lift up your hearts.” “We lift them up to the Lord.” “Let us give thanks to the Lord our God.” “It is right to give him thanks and praise.” In our own time, the General Instruction of the Roman Missal states that the dialogue between the celebrant and the faithful gathered together and the acclamations “are not simply outward signs of the community’s celebration, but . . . encourage and achieve a greater communion between priest and people.”
Susan K. Wood, “Liturgical Ecclesiology”, in A Church with Open Doors: Catholic Ecclesiology for the Third Millennium, Richard R. Gaillardetz and Edward P. Hahnenberg, eds. (Collegeville, MN: Liturgical Press, 2015): Loc 3430-3447.