Liturgical reforms of Pope Pius XII

The liturgical reforms of Pope Pius XII continued a process initiated by Pope Pius X, who began the process of encouraging the faithful to a meaningful participation in the liturgy. Pope Pius XII redefined liturgy in light of his previous encyclical "Mystici corporis" and reformed several liturgical practices in light of this teaching. The liturgical teaching of Pius XII is contained especially in his encyclical "Mediator Dei" of 1947. Although Pius XII felt compelled to reprove the desire for novelty among certain leaders of the Liturgical Movement, the liturgical reforms undertaken later in his pontificate were in fact relatively broad in their scope.
Groundwork.
On 20 November 1947, Pius issued the encyclical "Mediator Dei", the first encyclical devoted entirely to liturgy. Though it warned against excesses in the liturgical reform movement, it embraced many of its principles. It included the statement: "the use of the mother tongue in connection with several of the rites may be of much advantage to the people".
In 1948 the pope established a Pontifical Commission for the Reform of the Liturgy, appointing as its secretary Monsignor Annibale Bugnini, who served in positions of increasing responsibility for liturgy until 1975.
Eucharistic fast.
Pope Pius X had modified Eucharistic practice promoting the frequent reception of Communion in 1905 and lowering the age of First Communion in 1910. To encourage the reception of communion–and to associate attendance at Mass more closely with the reception of Communion–Pius XII changed the requirements for fasting before receiving communion in two stages. In 1953, by the Apostolic constitution "Christus Dominus", he continued to require fasting from midnight before receiving communion, but ruled that water did not break the fast. He also relaxed the fasting requirement for the sick and travelers, those engaged in exhausting physical labor, and for priests who celebrate several Masses on the same day. In 1957 he replaced the fast from midnight with a three-hour fast from solid food and alcohol and a one-hour fast from other liquids. Ordinary communicants would calculate the time until the moment they took communion; priests fasted based on the time they began saying Mass. The new fasting rules opened the way to scheduling evening Masses, which the fast from midnight regime made all but impossible for those desiring to receive Communion.
Use of the vernacular.
Permission for the use of the vernacular for parts of the Mass had been granted on occasion long before the papacy of Pius XII; including in 1906 by Pius X (parts of Yugoslavia), Benedict XV in 1920 (Croatian, Slovenian, and Czech), Pius XI in 1929 (Bavaria). 
Under Pius XII, the Sacred Congregation of Rites granted permission for the use of local languages in countries with expanding Catholic mission activities, including in Indonesia and Japan in 1941–2. In 1949 permission was granted for using Mandarin Chinese in Mass except for the Canon, and for the use of Hindi in India in 1950. Permission was also granted to use a French (1948) and German (1951) translation for rituals other than Mass.
As a means of increasing the participation of the congregation in the celebration of Mass, recognizing that joining in chant is not possible at a Mass that is "read" rather than sung, in 1958 Pius approved the use of hymns in the vernacular at appropriate points in the service. As a means to closer awareness by the congregation he also allowed the epistle and gospel to be read aloud by a layman while the celebrant read them quietly in Latin.
Though insisting on the primacy of Latin in the liturgy of the Western Church (cf. "Mediator Dei", par. 60), Pius approves the use of the vernacular in the Ritual for sacraments and other rites outside the Mass. All such permissions, however, were to be granted by the Holy See, and Pius XII strongly condemned the efforts of individual priests and communities to introduce the vernacular on their own authority. He allowed the use of the vernacular in other rites and sacraments outside the Mass, in the service for Baptism and Extreme Unction.
Liturgical Propers and other directives.
Following in the footsteps of his predecessors, Pius XII instituted a number of new feasts and approved new Propers. After defining the Dogma of the Assumption in 1950, a new mass formula (the mass "Signum magnum") was introduced for the feast, which falls on August 15. Pius XII also instituted the feast of the Immaculate Heart of Mary, which he established as a double of the second class and fixed to August 22, the octave day of the Assumption. Other new feasts included the feast of the Queenship of Mary (May 31) and the feast of Saint Joseph the Worker (to coincide with the socialist holiday of May 1), which thus replaced the Feast of Saint Joseph Patron of the Universal Church, observed until then (from 1870) as a movable feast on the third Wednesday after Easter. Pius XII added to the missal and breviary a new Common of Holy Pontiffs, in order to highlight the special role of the Roman pontiffs in the economy of the Church. Until then, holy popes had been commemorated liturgically using the same texts as other bishops. The new mass for holy pontiffs begins with the Introit "Si diligis me".
The Sacred Congregation of Rites had jurisdiction over the Rites and ceremonies of the Latin Church such as Holy Mass, sacred functions and divine worship. It issued the location of the blessed sacrament within the Church, to be always at the main altar in the centre of the Church. The Church should display religious objects, but not be overloaded with secondary items or even Kitsch. Modern sacred art should be reverential and still reflect the spirit of our time. Since 1942, Priests are permitted to officiate marriages without Holy Mass. They may also officiate confirmations in certain instances.
Easter Vigil.
Before the changes instituted by Pius XII, the Easter Vigil service was held on Holy Saturday morning. The part of the service devoted to the blessing of fire and entry into a dark sanctuary had not anticipated nor been adapted to modern lighting. The Liturgy of the word consisted of twelve readings. The conferral of baptism was envisaged, though rarely performed. This was followed by the Litany of the Saints and the celebration of an abbreviated Mass. The service concluded with an abbreviated Vespers service.
In 1951 on an experimental basis, and then permanently in 1956, Pope Pius XII introduced the Easter Vigil, a new celebration of Easter night He shifted the hour of the celebration to after sunset and restructured the service. The Paschal candle is the center of the service of new fire, rather than a three-branched candle, the arundo, that existed only for use in this service; the congregation lights its own candles as well, a participatory innovation. The water is blessed in front of the congregation, not at the baptismal font. Among many detailed changes, only four of the Old Testament readings were kept. Then followed only the first part of the Litany of the Saints and possible baptisms. A major innovation occurred with the incorporation of renewal of baptismal promises by the entire congregation, "a milestone" that introduced modern languages into the general Roman liturgy for the first time. The second part of the Litany followed. After this came Mass, slightly abbreviated followed by Easter lauds instead of Holy Saturday Vespers.
His re-introduction of the Easter Vigil was generally popular, although it faced a cool reception from some prelates. Cardinal Spellman of New York considered asking for a dispensation from performing the new Easter Vigil rite, but relented. Another assessment saw initial enthusiasm that lasted only a few years and concluded that only novelty had attracted attention in the first years. Other Christian denominations adopted the popular Roman Catholic Easter ceremonies in later years, an ecumenical influence of Pius XII.
Holy Week rites.
In 1955, Pius XII promulgated new liturgies for Holy Week in the decree "Maxima Redemptionis" (November 19, 1955). In addition to the new Easter Vigil, modified on an experimental basis in 1951 and now made permanent, he promulgated the rites for Palm Sunday, Holy Thursday and Good Friday, the most important ceremonies in the Roman liturgy. The Holy Thursday Mass of the Lord's Supper was moved from morning to evening to replicate more closely the experience of the historical Last Supper and the Good Friday liturgy similarly moved to the afternoon.
The new Good Friday liturgy modified the Good Friday prayer for the Jews in two ways. Pius had already, in 1949, made a public declaration that the Latin word "perfidus", which is applied to the Jewish people in this prayer, means "unbelieving", not "perfidious" or "treacherous". The 1955 liturgy rendered the text in English as "the faithless Jews". It also called for the congregation to kneel for a moment of silent prayer during this petition just as the congregation did during the other nine petitions in this liturgy.
Rubrics and liturgical calendar.
The rubrics and calendar of the Mass and the Divine Office were reformed by the constitution "Cum hac nostra aetate" (March 23, 1955). The reform to the calendar, the most dramatic before its complete overhaul in 1969, consisted mainly in the abolition of various octaves and vigils. An octave is the week-long prolongation of a great feast, either by the celebration of a proper Mass all through the Octave or by the addition of an additional Collect when the Mass of another feast is celebrated. Of the 18 octaves existing in the Roman calendar, all but three (Easter, Pentecost, Christmas) were purged in the reform, including the octaves of the Epiphany, Corpus Christi, the Ascension and the Immaculate Conception. A vigil is a day of liturgical preparation preceding a great feast. The reform of 1955 eliminated roughly half the vigils in the Roman calendar, including the vigil of the Epiphany and the vigils of the Apostles.
The ancient custom of beginning a feast with first Vespers on the eve of the feast was abolished, with certain exceptions. Following the reform, most feasts have only one set of Vespers (what had been known as second Vespers), celebrated on the afternoon of the feast itself. The purpose of this derogation of the ancient custom was to simplify the process by which a feast had to be commemorated when the second Vespers of one feast coincided with the first Vespers of the subsequent feast. The reform also abolished the custom whereby Vespers was to be recited before noon during Lent. This custom was a survival of the ancient custom whereby the Lenten fast could only be broken after Vespers; the Church had long since permitted this meal to be taken at mid-day and had thus also anticipated the office of Vespers during Lent.
Proper Last Gospels were also eliminated in the reform, with the exception of the third Mass of Christmas (when the Gospel of the Mass is taken from John 1) and at Low Masses on Palm Sunday. A "Proper Last Gospel" occurs when a commemoration is made at Mass of another feast (or feria or vigil or Sunday) of a high rank, whose Gospel is read at the end of Mass in place of the habitual Last Gospel (John 1: "In principio"). Prior to the reform of Pius XII, a proper Last Gospel was always said when a feast was celebrated instead of a feria of Lent, or a vigil, or a Sunday.
The manner of ranking feasts was also changed slightly. The reform of 1955 suppressed the rank known as the semi-double, leaving only doubles and simples. All semi-double feasts became simples, and all semi-double Sundays became doubles. Feasts ranked as simples prior to 1955 were reduced to commemorations; however, on ferias "per annum" on which the commemoration of a saint, formerly of simple rank, happened to fall, the celebrant was permitted to say the Mass of the commemorated saint in full as a festal Mass, while saying the Office of the feria with commemoration of the saint. (In 1960 John XXIII completely replaced the traditional manner of ranking feasts by abolishing the double, with its various grades, and the simple, and classifying feasts instead as first, second, third, or fourth class.)
In Masses for the dead that were not funeral Masses, the sequence "Dies Irae" was no longer required to be said before the Gospel; on All Souls' Day, on which it was customary for priests to say three separate Masses, priests were required to say the "Dies Irae" only at their first Mass of the day.
Greater limitations were placed upon the use of prefaces. The practice of saying the Preface of the Trinity on Sundays outside Christmastide, Lent, Passiontide, and Eastertide was retained; however, the prefaces for non-Sunday Masses were restricted to the Common Preface, seasonal prefaces, or prefaces proper to specific feasts. In practice, this rubrical change eliminated such traditional practices as the use of the Preface of the Nativity at the Masses of Corpus Christi and of the Transfiguration.
Finally, the supplementary prayers that had been recited in connection with the breviary were also suppressed. Thus, for example, the various seasonal Marian antiphons that had been recited at the end of the liturgical hours were retained only after Compline.
In his book "The Simplification of the Rubrics", explaining the changes, Monsignor Annibale Bugnini commented, "The present decree has a contingent character. It is essentially a bridge between the old and the new, and if you will, an arrow indicating the direction taken by the current restoration."
Other.
As the liturgical reform movement had long been exploring the history and form of concelebrating Mass, in 1956, Pius specified that all celebrants say the words of consecration aloud if they mean to participate fully, not just externally.