The Monday, Tuesday and Wednesday before the feast of the Ascension are Rogation Days or days of the 'Lesser Litanies', lesser as they are less ancient and celebrated with less solemnity than the 'Greater Litanies' celebrated on the 25th April.
On Monday of the Rogations the Office is of the ferial day. At Mattins a homily from St. Ambrose is read at the nocturn. At Lauds the antiphon on the Benedictus is proper, Petite, et accipietis etc., as is the collect Praesta, quaesumus etc. Following this collect a commemoration of St. Felix is sung followed by the Commemoration of the Cross. At the Hours all is taken from the ferial Psalter except the collect which is that which was sung at Lauds. At Prime the Domincal preces are sung.
After None the altar is vested in a violet antependium. The celebrant, vested in violet cope, assisted by deacon and subdeacon in violet dalmatic and tunicle reverence the altar then kneel and pray for a short while. They rise and the cantors begin the antiphon Exsurge Domine. The choir continue....adjuva nos, et libera nos, propter nomen tuam. Ps. Deus auribus nostris audivimus patres nostri annuntiaverunt nobis. Gloria Patri etc, Sicut erat etc and then Exsurge Domine is repeated. All all kneel (except the crucifer and acolytes who go and stand at the entrance of the choir) and the cantors then begin the Litany of the Saints. Each invocation is doubled, i.e. the cantors sing e.g. Pater de caelis, Deus, miserere nobis and this is repeated in its entirety by everyone else. When Sancta Maria, ora pro nobis has been repeated all rise and the Procession sets off.
The Procession goes outside of the Church and may visit other Churches on its route. In this case the celebrant is offered lustral water at the entrance to the church and processes to the High Altar. After a moment for silent prayer the choir signs the antiphon of the patron of the church, its versicle and response (with Alleluia added as it is Paschaltide) and the celebrant sings the collect of the Patron. The Litany is then resumed and the Procession continues. If the Procession has a long route the Litany, from Sancta Maria etc may be repeated or the Seven Penitential Psalms sung to the tonus in directum. When the Procession enters the church where Mass will be celebrated, lustral water is received on entering and the Procession goes to the sanctuary. All kneel as the Litany ends. The celebrant intones Pater noster etc and then the cantors sing psalm 69. After the versicles that follow the celebrant stands to sing the ten collects. He then kneels again as Exadiat nos etc is sung. The ministers then rise and the celebrant changes from a cope to chasuble and all put on their maniples. The Mass Exaudivit is then sung. The chants are those used for ferial Masses. The Gloria is not sung, the second collect is of St. Felix and the third collect is Concede nos. The dismissal is Benedicamus Domino.
Vespers are of the following feast of St. Angela Merici with a commemoration sung of St. Petronilla.
On Tuesday the Office of St. Angela Merici is sung and there is no commemoration of the Rogation Day in the Office. Mattins has three nocturns. At Lauds a commemoration of St. Petronilla is sung. When the Rogation Procession takes place the Mass Exaudivit is sung as detailed above for Monday. The second collect is of St. Angela Merici, the third collect is of St. Petronilla. Where the Rogation Procession does not take place the Mass Dilexisti is sung (for St. Angela Merici) with the second collect of the Rogation Mass, the third collect of St. Petronilla. Vespers are of the feast.
On Wednesday the Office of the Vigil of the Ascension is celebrated. At Mattins the homily is taken from the writings of St. Augustine. At Lauds the Commemoration of the Cross is sung after the collect of the Office (that of the preceding Sunday). At Prime the Dominical preces are sung. Mass is celebrated of the Vigil in white vestments with Gloria, the second collect of the Rogations, the third collect Concede nos and with the preface of Paschaltide. At None the Paschal Doxology is sung for the last time this year. When the Rogation Procession takes place the Mass Exaudivit is sung after None as detailed for Monday above. The second collect is of the Vigil, the third collect Concede nos and the last Gospel of the Vigil. Vespers are first Vespers of the Ascension.
Those obliged to the Office who do not take part in Rogation Processions must say the Litany on the three days.
In the 'liturgical books of 1962' when the Rogation Procession takes place the Litany may be sung in the vernacular if the faithful are present. The petitions are not duplicated. In the votive Mass that follows all the 'preparatory prayers' i.e. In nomine Patris..., Introibo ad altare Dei..., Judica me Deus..., Confiteor Deo..., the versicles, Aufer a nobis... and Oramus te, Domine are all cut out. The dismissal is Ite, missa est.