IV class
White
IV class Requiem Masses are not permitted during the IV class ferial days of Christmastide and Epiphanytide.
Mass as on 1 January; Gloria; no Credo; preface of the Nativity without proper Communicantes
Nota bene: The principal parts of the office during these seasonal ferias are from January 1, but are all listed together for convenience in the Ordinarium, under Time of the Nativity.
Matins: Invitatorium and Hymn from the Time of the Nativity; psalms and antiphons of the feria; scripture lessons proper to January 3; Te Deum
Lauds: Psalms and antiphons of the feria; capitulum and following from Time of the Nativity
Prime: Verse Qui natus es
Hours: Psalms and antiphons of the feria; capitulum and following from Time of the Nativity
Vespers: Psalms and antiphons of the feria; capitulum and following from Time of the Nativity