The Mass and its settings draw their name from the introit of the liturgy, which begins with the words ""Requiem aeternam dona eis, Domine"" (Latin for "Eternal rest grant them, O Lord"), which is cited from 2 Esdras—"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.