Pope Pius X in the context of "Encyclical"

The 1917 Code of Canon Law (abbreviated 1917 CIC, from its Latin title Codex Iuris Canonici), also referred to as the Pio-Benedictine Code, is the first official comprehensive codification of Latin canon law.

Ordered by Pope Pius X in 1904 and carried out by the Commission for the Codification of Canon Law, led by Pietro Cardinal Gasparri, the work to produce the code was completed and promulgated under Pope Benedict XV on 27 May 1917, coming into effect on 19 May 1918. The 1917 Code of Canon Law has been described as "the greatest revolution in canon law since the time of Gratian" (1150s AD).

Thomism is the philosophical and theological school which arose as a legacy of the work and thought of Thomas Aquinas (1225–1274), the Dominican philosopher, theologian, and Doctor of the Church.

In philosophy, Thomas's disputed questions and commentaries on Aristotle are perhaps his best-known works. In theology, his Summa Theologica is amongst the most influential documents in medieval theology and continues to be the central point of reference for the philosophy and theology of the Catholic Church. In the 1914 motu proprio Doctoris Angelici, Pope Pius X cautioned that the teachings of the Church cannot be understood without the basic philosophical underpinnings of Thomas's major theses:

Our Lady of San Juan de los Lagos (English: Our Lady of Saint John of the Lakes) is a Roman Catholic title of the Blessed Virgin Mary venerated by Mexican and Texan faithful. The original image is a popular focus for pilgrims and is located in the state of Jalisco, in central Mexico, 122 kilometers (76 mi) northeast of the city of Guadalajara. The statue is venerated both in Mexico and in the United States where it is known by its proxy title Nuestra Señora de San Juan del Valle (Our Lady of Saint John of the Valley), mainly focused in Texas.

Pope Pius X granted the image a Pontifical decree of Canonical coronation on 29 January 1904. The rite of coronation was executed on 15 August 1904 via the Archbishop of Guadalajara, Jose de Jesus Ortiz y Rodriguez.

In the Catholic Church, a consistory is a formal meeting of the College of Cardinals called by the pope. There are two kinds of consistories, extraordinary and ordinary. An "extraordinary" consistory is held to allow the pope to consult with the entire membership of the College of Cardinals. An "ordinary" consistory is ceremonial in nature and is normally attended by cardinals resident in Rome. For example, the pope elevates new cardinals to the College at a consistory; Pope Francis called consistories for ceremonies of canonization; and Pope Benedict announced his decision to retire in 2013 at a consistory.

A meeting of the College of Cardinals to elect a new pope is not a consistory, but a conclave.

Modernism in the Catholic Church describes attempts to reconcile Catholicism with modern culture, specifically an understanding of the Bible and Sacred Tradition in light of the historical-critical method and new philosophical and political developments of the late 19th and early 20th centuries.

The term modernism—generally used by its critics rather than by adherents of positions associated with it—came to prominence in Pope Pius X's 1907 encyclical Pascendi Dominici gregis, where he condemned modernism as "the synthesis of all heresies".

An antiphonary or antiphonal is one of the liturgical books intended for use in choro (i.e. in the liturgical choir), and originally characterized, as its name implies, by the assignment to it principally of the antiphons used in various parts of the Latin liturgical rites.

Medieval antiphonaries varied with regional liturgical tradition. In 1570, following the Council of Trent, the Roman Rite antiphonary was declared universal. The Roman Antiphonary (Antiphonale Romanum) contains the chants for the canonical hours for the hours of Lauds, Prime, Terce, Sext, None, Vespers and Compline for every day of the year. The Vesperale Romanum is an excerpt of the Antiphonary containing the chants sung at Vespers. The music for use at the Mass is contained in the Roman Gradual (Graduale Romanum), the chants of the ordinary are also edited as an excerpt from the Gradual, the Kyriale Romanum. The Antiphonale Romanum was substantially revised in 1910–11 in the course of the reform of the Roman Breviary under Pope Pius X, notably restoring authentic Gregorian melodies. For the 1971 "Liturgy of the Hours", there are two volumes, Antiphonale Romanum II and Liber Hymnarius.

Acta Apostolicae Sedis (Latin for 'Acts of the Apostolic See'), often cited as AAS, is the official gazette of the Holy See, appearing about twelve times a year. It was established by Pope Pius X on 29 September 1908 with the decree Promulgandi Pontificias Constitutiones, and publication began in January 1909. It contains all the principal decrees, encyclical letters, decisions of Roman congregations, and notices of ecclesiastical appointments. The laws contained in it are to be considered promulgated when published, and effective three months from date of issue, unless a shorter or longer time is specified in the law.