Catechism of the Catholic Church 1348
All gather together. Christians come together in one place
for the Eucharistic assembly. At its head is Christ himself, the
principal agent of the Eucharist. He is high priest of the New
Covenant; it is he himself who presides invisibly over every
Eucharistic celebration. It is in representing him that the bishop or
priest acting in the person of Christ the head (in persona Christi capitis)
presides over the assembly, speaks after the readings, receives the
offerings, and says the Eucharistic Prayer. All have their own active
parts to play in the celebration, each in his own way: readers, those
who bring up the offerings, those who give communion, and the
whole people whose “Amen” manifests their participation.
Catechism of the Catholic Church 1143
For the purpose of assisting the work of the common
priesthood of the faithful, other particular ministries also exist, not
consecrated by the sacrament of Holy Orders; their functions are
determined by the bishops, in accord with liturgical traditions and
pastoral needs. “Servers, readers, commentators, and members of
the choir also exercise a genuine liturgical function.”14
Catechism of the Catholic Church 1350
The presentation of the offerings (the Offertory). Then,
sometimes in procession, the bread and wine are brought to the
altar; they will be offered by the priest in the name of Christ in the
Eucharistic sacrifice in which they will become his body and blood.
It is the very action of Christ at the Last Supper—“taking the bread
and a cup.” “The Church alone offers this pure oblation to the
Creator, when she offers what comes forth from his creation with
thanksgiving.”177 The presentation of the offerings at the altar
takes up the gesture of Melchizedek and commits the Creator’s
gifts into the hands of Christ who, in his sacrifice, brings to perfec
tion all human attempts to offer sacrifices.
General Instruction of the Roman Missal 100
In the absence of an instituted acolyte, there may be deputed lay ministers to serve at the altar and assist the Priest and the Deacon; these carry the cross, the candles, the thurible, the bread, the wine, and the water, or who are even deputed to distribute Holy Communion as extraordinary ministers.