Eternal Rest (Requiem Aeternam)

"Eternal rest grant unto them, O Lord" — Requiem æternam — is the great antiphon of the Church for her departed children, and one of the most constantly repeated prayers in all of Catholic devotion. From it the whole Requiem Mass takes its name: the very first word sung at the Introit is Requiem, the Latin for rest, and so the Mass for the dead has been called ever since.

The words themselves are ancient. They echo the imagery of 4 Esdras (2:34–35) — a promise of everlasting rest, and of a light that shall shine upon the blessed for evermore — a writing that is not part of the canonical Scriptures but was printed as an appendix to the Latin Vulgate and drawn upon by the liturgy. The Church took up its imagery of rest and unfailing light to express her twofold prayer for the holy souls: that they may be freed from every trace of sin and admitted to the vision of God, who is Himself the light that never fades.

The prayer rests on a doctrine as old as the faith itself: that it is right and profitable to pray for the dead. "It is therefore a holy and wholesome thought to pray for the dead, that they may be loosed from sins," wrote the author of the Second Book of Machabees (12:46) — the Scripture on which the Church's teaching on Purgatory and intercession for the departed most plainly stands. The souls in Purgatory can no longer help themselves; the living can help them, above all by the Holy Sacrifice of the Mass, but also by this simple antiphon offered from the heart.

So the Requiem æternam is said everywhere: as the versicle repeated through the Office of the Dead, at the graveside, at the end of the Rosary, and daily by the faithful for their departed. Its closing words — Requiéscant in pace, "May they rest in peace" — abbreviated R.I.P., have become the epitaph of Christendom itself.