Requiem aeternam

A Requiem or Requiem Mass, also known as Mass for the dead (Latin: Missa pro defunctis) or Mass of the dead (Latin: Missa defunctorum), is a Mass in the Catholic Church offered for the repose of the soul or souls of one or more deceased persons, using a particular form of the Roman Missal. It is frequently, but not necessarily, celebrated in the context of a funeral.

Musical settings of the propers of the Requiem Mass are also called Requiems, and the term has subsequently been applied to other musical compositions associated with death, dying, and mourning, even when they lack religious or liturgical relevance.

The term is also used for similar ceremonies outside the Roman Catholic Church, especially in the Anglo-Catholic tradition of Anglicanism and in certain Lutheran churches. A comparable service, with a wholly different ritual form and texts, exists in the Eastern Orthodox and Eastern Catholic Churches, as well as in the Methodist Church.

The Mass and its settings draw their name from the introit of the liturgy, which begins with the words "Requiem aeternam dona eis, Domine" – "Grant them eternal rest, O Lord". ("Requiem" is the accusative singular form of the Latin noun requies, "rest, repose".) The Roman Missal as revised in 1970 employs this phrase as the first entrance antiphon among the formulas for Masses for the dead, and it remains in use to this day.

In earlier forms of the Roman Rite, some of which are still in use, a Requiem Mass differs in several ways from the usual Mass in that form. Some parts that were of relatively recent origin, including some that have been excluded in the 1970 revision, are omitted. Examples are the psalm Iudica at the start of Mass, the prayer said by the priest before reading the Gospel (or the blessing of the deacon, if a deacon reads it), and the first of the two prayers of the priest for himself before receiving Communion. Other omissions include the use of incense at the Introit and the Gospel, the kiss of peace, lit candles held by acolytes when a deacon chants the Gospel, and blessings. There is no Gloria in excelsis Deo and no recitation of the Creed; the Alleluia chant before the Gospel is replaced by a Tract, as in Lent; and the Agnus Dei is altered. Ite missa est is replaced with Requiescant in pace (May they rest in peace); the "Deo gratias" response is replaced with "Amen". Black is the obligatory liturgical colour of the vestments in the earlier forms, while the later form allows a choice between black and violet, and in some countries, such as England and Wales, white. The sequence Dies Irae, recited or sung between the Tract and the Gospel, is an obligatory part of the Requiem Mass in the earlier forms. As its opening words Dies irae ("day of wrath") indicate, this poetic composition speaks of the Day of Judgment in fearsome terms; it then appeals to Jesus for mercy.

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