In the Roman rite liturgy of the Catholic Church, the term solemnity is used to indicate those celebrations of the mysteries of the life of Christ and of the saints that have greater liturgical importance.
The term solemnity was introduced in the Missal with the liturgical reform. In the previous Missal, the most important recurrences of the liturgical year are the first-class feasts.
Dates in the liturgical calendar
They have the degree of solemnity:
the Immaculate Conception (December 8)
Christmas (December 25)
Mary Most Holy Mother of God (January 1)
Epiphany (January 6)
Saint Joseph Spouse of the Blessed Virgin (March 19)
the Annunciation of the Lord (March 25)
the Nativity of St. John the Baptist (June 24)
Saints Peter and Paul (June 29)
the Assumption of Mary (15 August)
All Saints (November 1)
Our Lord Jesus Christ King of the Universe (last Sunday of the liturgical year).
and mobile solemnities:
Easter of resurrection;
the Ascension of Jesus (40th day after Easter, or the 7th Sunday after Easter)
Pentecost (fiftieth day after Easter)
the Holy Trinity (first Sunday after Pentecost)
Corpus Domini (Thursday after the first Sunday after Pentecost, or the second Sunday after Pentecost)
the Sacred Heart of Jesus (Friday after the second Sunday following Pentecost) The patron saint and the anniversary of the dedication of the church are also celebrated as solemnities. Furthermore, the Bishops' Conferences have the faculty to request the institution of other solemnities specific to the region.
Solemnities take precedence over any other recurrence and Sundays, with the exception of the Sundays of Advent, Lent and Easter, Ash Wednesday, Holy Week and the Octave of Easter. However, since solemnities can never be ignored, in case of occurrence (coincidence of two recurrences), solemnities are celebrated on the first available day following that occupied by the celebration of a higher degree: it often happens for the solemnity of the Annunciation which, if March 25 falls on a Sunday in Lent, it is celebrated on Monday March 26; or if March 25 falls in Holy Week or in the Octave of Easter, it is celebrated on the Monday after the second Sunday of Easter (sometimes, therefore, also in the month of April).
Even the solemnity of St. Joseph (March 19) can interfere with the Lenten period: if it is prevented by a Sunday in Lent, the general rule of celebration follows the following day (Monday March 20). However, if instead it is prevented by Holy Week, the celebration is not postponed but anticipated to the Saturday preceding Palm Sunday.
A particular case is constituted by the solemnity of the Immaculate Conception, the date of which may coincide with a Sunday in Advent. For this solemnity (which strictly speaking under similar conditions should be celebrated on December 9), because of popular devotion, an exemption for Italy has always been granted by the Congregation for Divine Worship and the Discipline of the Sacraments, thus granting the celebration on the proper day on condition that some parts of the liturgy proper to the solemnity are replaced by the liturgy proper to the Sunday of Advent (e.g. the second reading).
In the event of occurrence of a solemnity of the same degree, the celebration with greater significance takes precedence: for example, the mobile solemnity of the Sacred Heart of Jesus (Solemnity of the Lord), if it falls on June 24 or June 29, would take the place respectively of the Nativity of St. John the Baptist and of Saints Peter and Paul (Solemnity of Saints), whose celebration for that year would be anticipated to the previous day (June 23 or June 28), to allow the celebration of the memory of the Immaculate Heart of Mary, which it falls on the Saturday after (the following day) the Sacred C