Dies Irae (Day of Wrath) is a famous thirteenth century Latin hymn thought to be written by Thomas of Celano. It is a medieval 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 was used as a sequence in the Roman Catholic Requiem Mass until the 1970 revision of the Roman Missal.