Liturgy of the Eucharist & Concluding Rites
Preparation of the Gifts
"The procession bringing the gifts is accompanied by the Offertory chant (cf n 37b), which continues at least until the gifts have been placed on the altar...Singing may always accompany the rite at the offertory, even when there is no processions with the gifts. (n 74).
The Song needs to last throughout the whole collection-taking process and as the Missal states, the minimum ending spot is when the gifts are placed on the altar, but the IDEAL is that singing go through all the way through the washing of the hands.
The Eucharistic Prayer
"Now the center and summit of the enter celebration begins:..." (n. 78)
Ideally many portions of this prayer are to be sung or chanted. This will be in part dictated by the comfort level of the priest presider with his own parts.
This is to be sung (Ideal) or recited with the entire congregation. The words of this text are not to be changed.
This is to be sung (Ideal) or recited with the entire congregation. The words of this text are not to be changed. There are three forms found within the Missal.
This is the actual high point of the Eucharistic Celebration and it needs to be shown as such through song. Ideally all is sung, including the priest's part. The people respond with the "Great Amen". This Amen ought to be a joyous acclamation.
This is when the priest breaks the bread and places hosts within the various patens. Music is needed to cover this action and the Church sings the Agnus Dei, aka, the "Lamb of God". The song goes on as long as needed until the priest has finished breaking the bread and finished his silent prayers. What is to be sung is the same verse," Lamb of God, who takes away the sin of the world, have mercy on us." until the final verse, which ends"..grant us peace." No other verses are permitted to be sung.
A song or songs are used to cover the motion of the distribution of Holy Communion. The song is begun from when the Priest receives communion (n.86) and continues throughout until all have received and the altar is cleared. Ideally the choir would receive after all the people have received. When communion is complete, a post communion song may be included. (n.88).
The recessional hymn begins after the priest or bishop announces the dismissal "The Mass is ended, Go in peace." It covers the procession of the priest and liturgical ministers and may go as long as needed.