I class
White and Red
No commemoration of St. Peter Celestine, Pope and Confessor
The color is White for the Offices up to and excluding the Mass. The color is Red for the Mass and subsequent Offices.
The Mass is as usual, beginning with the prayers at the foot of the altar, omitting the blessing of the font, which is found in older editions of the Missal.
Mass of the Vigil (Red), Gloria, no Credo, preface of the Holy Ghost (with hodierna die), Communicantes and Hanc igitur proper.
Note: The reason hodierna die in the Preface and the proper Communicantes and Hanc Igitur are used already at the Vigil is because the Pentecost Vigil historically mirrored the Paschal Vigil very closely and was celebrated Saturday night, leading into Sunday.
Matins: Invitatorium and Hymn in Tempore Ascensionis, antiphon Alleluia and psalms of Saturday, three lessons proper (homilia in evangelium diei), Te Deum
Lauds: Antiphon Alleluia and psalms of Saturday (first schema); remainder in Tempore Ascensionis; oration of the preceding Sunday; no preces
Hours: Antiphon Alleluia and psalms of Saturday; remainder in Tempore Ascensionis; oration of the preceding Sunday
I Vespers: Of Pentecost; proper antiphons, with psalms of Sunday except Psalm 116 for fifth psalm; remainder proper
Compline: Of Sunday