Ranking of liturgical days in the Roman Rite

Ranking of liturgical days in the Roman Rite serves two purposes. The rank indicates some particular points about the manner of celebrating the day: for instance, the Mass of a Solemnity will include recitation of the Gloria in Excelsis and the Creed, that of what is now called in a specific technical sense a Feast will have the Gloria but not the Creed, and a Memorial will have neither, although it may have proper readings. The other purpose is to determine which Mass is to be said when two feasts coincide (or "occur") on the one day, as well as when a feast falls on a Sunday or certain other privileged days.

Each day in the Catholic liturgical calendar has a rank. The five basic ranks for the Ordinary Form of the Roman Rite, in descending order of importance, are as follows:

The ranking of feast days of saints and of Christian mysteries such as the Ascension of the Lord, which had grown from an original division between doubles and simples developed into a more complicated hierarchy of Simple, Semidouble, and Double, with feast days of the Double Rite further divided into Double of the I Class, Double of the II Class, Greater Double or Major Double, and Double, in order of descending rank.

What the original meaning of the term "double" may have been is not entirely certain. Some think that the greater festivals were thus styled because the antiphons before and after the psalms were "doubled", i.e. twice repeated entire on these days. Others, with more probability, point to the fact that before the ninth century in certain places, for example at Rome, it was customary on the greater feast days to recite two sets of Matins, the one of the feria or week-day, the other of the festival. Hence such days were known as "doubles".

The Catholic Encyclopedia of 1907 shows the incremental crowding of the calendar with the following table based on the official revisions of the Roman Breviary in 1568, 1602, 1631 and 1882, and on the situation in 1907.

In 1907, when, in accordance with the rules in force since the time of Pope Pius V, feast days of any form of double, if impeded by "occurrence" (falling on the same day) with a feast day of higher class, were transferred to another day, this classification of feast days was of great practical importance for deciding which feast day to celebrate on any particular day. Pope Pius X simplified matters considerably in his 1911 reform of the Roman Breviary. In the case of occurrence the lower-ranking feast day could become a commemoration within the celebration of the higher-ranking one. Further retouches were made by Pope Pius XII in 1955,Pope John XXIII in 1960, and Pope Paul VI in 1969.

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