Dies Irae (Day of Wrath) is a famous thirteenth century Latin hymn thought to be written by Thomas of Celano. It is a meieval Latin poem, differing from classical Latin by its accentual (non-quantitative) stress and its rhymed lines. The meter is trochaic. The poem describes the day of judgment, the last trumpet summoning souls before the throne of God, where the saved will be delivered and the unsaved cast into eternal flames. The hymn is used as a sequence in the Roman Catholic Requiem Mass in the extraordinary form (1962 missal). It is not used in the ordinary form (1970) of the Roman Missal.