Catholic Church

An episcopal polity, also known as episcopalianism, is a hierarchical form of church governance in which the chief local authorities are called bishops. The word "bishop" here is derived via the British Latin and Vulgar Latin term *ebiscopus/*biscopus, from Ancient Greek ἐπίσκοπος (epískopos) 'overseer'. It is the structure used by many of the major Christian Churches and denominations, such as the Catholic, Eastern Orthodox, Oriental Orthodox, Church of the East, Anabaptist, Lutheran, and Anglican churches or denominations, and other churches founded independently from these lineages. Many Methodist denominations have a form of episcopal polity known as connexionalism.

A deacon is a member of the diaconate, an office in Christian churches that is generally associated with service of some kind, but which varies among theological and denominational traditions.

Major Christian denominations, such as the Catholic Church, the Oriental Orthodox Churches, the Eastern Orthodox Church, Lutheranism, Presbyterianism, Methodism, and Anglicanism, view the diaconate as an order of ministry.

In Christianity, a minister is a person authorised by a church or other religious organization to perform functions such as teaching of beliefs; leading services such as weddings, baptisms or funerals; or otherwise providing spiritual guidance to the community. The term is taken from Latin minister ("servant", "attendant"). In some church traditions the term is usually used for people who have been ordained, but in other traditions it can also be used for non-ordained.

In the Catholic Church, the Eastern Orthodox Church, the Oriental Orthodox Church, Anglicanism and Lutheranism, the concept of a priesthood is emphasized, though in the Church of England there are nearly as many non-ordained licensed lay ministers as there are paid clergy. In other traditions such as Baptist, Methodist, and Reformed groups like Congregationalists and Presbyterians, the term "minister" usually refers to a member of the ordained clergy who leads a congregation or participates in a role in a parachurch ministry; such a person may serve as an elder (presbyter), pastor, preacher, bishop, or chaplain.

In ecclesiology, the Christian Church is what different Christian denominations conceive of as being the true body of Christians or the original institution established by Jesus Christ. "Christian Church" has also been used in academia as a synonym for Christianity, despite the fact that it is composed of multiple churches or denominations, many of which hold a doctrinal claim of being the one true church to the exclusion of the others.

For many Protestant Christians, the Christian Church has two components: the church visible, institutions in which "the Word of God purely preached and listened to, and the sacraments administered according to Christ's institution", as well as the church invisible—all "who are truly saved" (with these beings members of the visible church). In this understanding of the invisible church, "Christian Church" (or catholic Church) does not refer to a particular Christian denomination, but includes all individuals who have been saved. This is in contrast to the one true church applied to a specific concrete Christian institution, a Christian ecclesiological position maintained by the Catholic Church, the Lutheran Churches, the Eastern Orthodox Church, the Oriental Orthodox churches, Assyrian Church of the East, and the Ancient Church of the East. While holding this view, the Lutheran Churches teach that "there are indeed true Christians in other churches" as "other denominations also preach the Word of God, though mixed with error". The branch theory, which is maintained by some Anglicans, holds that those Churches that have preserved apostolic succession are part of the true Church, though the majority of Anglicanism has historically "followed the major continental Reformers in their doctrine of the true church, identifiable by the authentic ministry of word and sacrament, in their rejection of the jurisdiction of the pope, and in their alliance with the civil authority ('the magistrate')".

Vatican City, officially the Vatican City State (Italian: Stato della Città del Vaticano; Latin: Status Civitatis Vaticanae), often shortened as the Vatican, is a landlocked sovereign city-state. Ruled by the pope, it is an enclave within Rome and serves as the administrative centre of the Catholic Church. Vatican City is governed by the See of Rome, commonly known as the Holy See, itself a sovereign entity under international law, which maintains its temporal power, governance, diplomacy, and spiritual independence. Vatican is also used as a metonym for the Holy See, which is the central governing body of the Catholic Church and Vatican City, comprising the pope and the Roman Curia. The independent state of Vatican City came into existence in 1929 via the Lateran Treaty between the Holy See and the Kingdom of Italy, which spoke of it as a new creation, not as a vestige of the much larger Papal States (756–1870), which had previously encompassed much of Central Italy.

With an area of 48.99 hectares (121 acres) and a population of about 882 in 2024, it is the smallest sovereign state in the world both by area and by population. It is among the least populated capitals in the world. As governed by the Holy See, Vatican City State is an ecclesiastical or sacerdotal-monarchical state ruled by the pope, who is the bishop of Rome and head of the Catholic Church; the highest state functionaries are all Catholic clergy of various origins. The Holy See dates to early Christianity and is the principal episcopal see of the Catholic Church, which in 2018 had about 1.329 billion baptized Catholics in the world, in the Latin Church and 23 Eastern Catholic Churches. After the Avignon Papacy (1309–1377) the popes have mainly resided at the Apostolic Palace within what is now Vatican City, although at times residing instead in the Quirinal Palace in Rome or elsewhere.

Papal primacy, also known as the primacy of the bishop of Rome, is an ecclesiological doctrine in the Catholic Church concerning the respect and authority that is due to the pope from other bishops and their episcopal sees. While the doctrine is accepted at a fundamental level by both the Catholic Church (Eastern and Western) and the Eastern Orthodox Church, the two disagree on the nature of primacy.

English academic and Catholic priest Aidan Nichols wrote that "at root, only one issue of substance divides the Eastern Orthodox and the Catholic Churches, and that is the issue of the primacy." French Eastern Orthodox researcher Jean-Claude Larchet wrote that, together with the Filioque controversy, differences in interpretation of this doctrine have been and remain the primary causes of schism between the Catholic Church and the Eastern Orthodox Church. In the Eastern Orthodox churches, some understand the primacy of the bishop of Rome to be merely one of greater honour, regarding him as primus inter pares ("first among equals"), without effective power over other churches. A prominent 20th century Eastern Orthodox Christian theologian, Fr. Alexander Schmemann, envisioned a primacy that sums up rather than rules over: "Primacy is power, but as power it is not different from the power of a bishop in each church. It is not a higher power but indeed the same power, only expressed, manifested, and realized by one."

Apostolic succession is the method whereby the ministry of the Christian Church is considered by some Christian denominations to be derived from the apostles by a continuous succession, which has usually been associated with a claim that the succession is through a series of bishops. Those of the Catholic, Eastern Orthodox, Oriental Orthodox, Church of the East traditions maintain that a bishop's orders are neither regular nor valid without consecration through apostolic succession. These traditions do not always consider the episcopal consecrations of all of the other traditions as valid.

This series was seen originally as that of the bishops of a particular see founded by one or more of the apostles. According to historian Justo L. González, apostolic succession is generally understood today as meaning a series of bishops, regardless of see, each consecrated by other bishops, themselves consecrated similarly in a succession going back to the apostles. According to the Joint International Commission for Theological Dialogue Between the Catholic Church and the Orthodox Church, "apostolic succession" means more than a mere transmission of powers. It is succession in a church which witnesses to the apostolic faith, in communion with the other churches, witnesses of the same apostolic faith. The "see (cathedra) plays an important role in inserting the bishop into the heart of ecclesial apostolicity", but once ordained, the bishop becomes in his church the guarantor of apostolicity and becomes a successor of the apostles.

The Keys of Heaven, also called Saint Peter's keys, refers to the metaphorical keys of the office of Saint Peter, the keys of the Gates of Heaven, or the keys of the kingdom of Heaven. It is explicitly referenced in the Bible in Matthew 16:19.

Pope Leo XIV (born Robert Francis Prevost, September 14, 1955) is the head of the Catholic Church and sovereign of Vatican City. He is the first pope to have been born in the United States, the first to hold either U.S. or Peruvian citizenships, the first from the Order of Saint Augustine, and the second (after his immediate predecessor Pope Francis) from the Americas.

Prevost was born in Chicago and raised in the nearby suburb of Dolton, Illinois. He became a friar in the Order of Saint Augustine in 1977 and was ordained as a priest in 1982. He earned a Doctor of Canon Law (JCD) degree in 1987 from the Pontifical University of Saint Thomas Aquinas in Rome. His service includes extensive missionary work in Peru in the 1980s and 1990s—he worked there as a parish pastor, diocesan official, seminary teacher, and administrator. Elected prior general of the Order of Saint Augustine, he was based in Rome from 2001 to 2013, and traveled extensively as part of this work, including to the order's many provinces and missions around the world. He then returned to Peru as Bishop of Chiclayo from 2015 to 2023. In 2023, Pope Francis appointed him prefect of the Dicastery for Bishops in Rome, and president of the Pontifical Commission for Latin America.

Interfaith dialogue, also known as interreligious dialogue, refers to cooperative, constructive, and positive interaction between people of different religious traditions (i.e., "faiths") or spiritual or humanistic beliefs, at both the individual and institutional levels.

Throughout the world, there are local, regional, national and international interfaith initiatives; many are formally or informally linked and constitute larger networks or federations. These include organisations such as the United Religions Initiative, the Parliament of the World's Religions, and interfaith training institutions like OneSpirit Interfaith Foundation in the United Kingdom, which since 1996, has prepared interfaith ministers for community service, spiritual accompaniment, and inclusive ceremony.