Postcommunion

Postcommunion (Latin: Postcommunio) is the text said or sung on a reciting tone following the Communion of the Mass.

Every Postcommunion (and secret) corresponds to a collect. These are the three fundamental prayers of any given Proper Mass. The Postcommunion is said or chanted exactly like the Collect. First comes that of the Mass celebrated; then, if other Masses are commemorated, their Postcommunions follow in the same order and with the same final conclusion as the collects.

After the Communion, when the celebrant has arranged the chalice, he goes to the epistle side and reads the Communion antiphon. He then comes to the middle and says or sings "Dominus Vobiscum" ("The Lord be with you"; in the early Middle Ages he did not turn to the people this time), goes back to the Epistle side, and says or sings one or more Postcommunions, exactly as the collects.

At ferial Masses in Lent the Oratio super populum follows the last Postcommunion. The celebrant sings Oremus; the deacon turning towards the people chants: Humiliate capita vestra Deo, on do with the cadence la, do, si, si, do for the last five syllables. Meanwhile, everyone, including the celebrant, bows the head. The deacon turns towards the altar and the celebrant chants the prayer appointed in the Mass. At low Mass the celebrant himself says the same text and does not turn towards the people. The deacon's exclamation apparently was introduced when this prayer became a speciality of Lent (Durandus mentions it).

The prayer after communion was mentioned in the first century Didache document.

The Communion act finishes the essential Eucharistic service, and early Masses, as described by Justin Martyr, did not have anything afterward. However, prayers were later added. The earliest complete liturgy extant, that of the "Apostolic Constitutions", contains two such prayers, a thanksgiving and a blessing.

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