General Roman Calendar of Pope Pius XII

In 1955 Pope Pius XII made several changes to the General Roman Calendar of 1954, changes that remained in force only until 1960, when Pope John XXIII, on the basis of further recommendations of the commission that Pius XII had set up, decreed a further revision of the General Roman Calendar (see General Roman Calendar of 1960). The changes made by Pope Pius XII thus remained unaltered for only five years.

He made the following changes by the decree "Cum nostra hac aetate" (De rubricis ad simpliciorem formam redigendis) of 23 March 1955

The grade and rite of "Semi-Double" was suppressed, and the liturgical days formerly celebrated as that rite were to be celebrated in the simple rite except the Vigil of Pentecost which was raised to the double rite.

The Sundays of Advent and Lent and those that follow up to Low Sunday, and also Pentecost Sunday, were to be celebrated as doubles of the first class, outranking all feasts; but when feasts of the first class occurred on the second, third or fourth Sunday of Advent, Masses of the feast were permitted except the conventual Mass. Sundays previously celebrated in the Semi-Double rite were raised to the Double rite. An impeded Sunday Office and Mass was to be neither anticipated nor resumed. A feast or title or any mystery of Our Lord falling on a Sunday per annum was thenceforth to take the place of the Sunday, with the latter merely commemorated.

The Vigil of the Nativity of the Lord and the vigil of Pentecost were privileged vigils. The Vigils of the Ascension of Our Lord, the Assumption of the Blessed Virgin Mary, Saint John the Baptist, Saints Peter and Paul and Saint Lawrence were to be common vigils and, if they occurred on a Sunday, were not to be anticipated, but simply omitted. All other vigils, including those marked in particular calendars, were suppressed.

Only the Octaves of Easter, Christmas and Pentecost were to be celebrated; all others occurring either in the universal or in particular calendars were suppressed. The days within the Easter and Pentecost octaves were raised to the Double rite, had precedence over all feasts, and did not admit commemorations. But the days of the Octave of Christmas, although of the Double rite, continued to be celebrated as before.

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