Papal infallibility in the context of Catholic Church

The infallibility of the Church is the belief that the Holy Spirit preserves the Christian Church from errors that would contradict its essential doctrines. It is related to, but not the same as, indefectibility, that is, "she remains and will remain the Institution of Salvation, founded by Christ, until the end of the world." The doctrine of infallibility is premised on the authority Jesus granted to the apostles to "bind and loose" (Matthew 18:18; John 20:23) and in particular the promises to Peter (Matthew 16:16–20; Luke 22:32) in regard to papal infallibility.

The terms Old Catholic Church, Old Catholics, Old-Catholic churches, or Old Catholic movement, designate "any of the groups of Western Christians who believe themselves to maintain in complete loyalty the doctrine and traditions of the undivided church but who separated from the See of Rome after the First Vatican Council of 1869–70".

The expression Old Catholic has been used from the 1850s by communions separated from the Roman Catholic Church over certain doctrines, primarily concerned with papal authority and infallibility. Some of these groups, especially in the Netherlands, had already existed long before the term. The Old Catholic Church is separate and distinct from Traditionalist Catholicism.

Franz Clemens Honoratus Hermann Josef Brentano (/brɛnˈtɑːnoʊ/; German: [bʁɛnˈtaːno]; 16 January 1838 – 17 March 1917) was a German philosopher and psychologist. His 1874 Psychology from an Empirical Standpoint, considered his magnum opus, is credited with having reintroduced the medieval scholastic concept of intentionality into contemporary philosophy.

Originally a Catholic priest, Brentano withdrew from the priesthood in 1873 due to the dogmatic definition of papal infallibility in Pastor aeternus. Working subsequently as a non-denominational professor, his teaching triggered research in a wide array of fields such as linguistics, logic, mathematics and experimental psychology through the young generation of philosophers who were gathered as the School of Brentano.

Pope Pius IX (Italian: Pio IX; born Giovanni Maria Battista Pietro Pellegrino Isidoro Mastai-Ferretti; 13 May 1792 – 7 February 1878) was head of the Catholic Church from 1846 to 1878. His reign of nearly 32 years is the longest verified of any pope in history and second only to Saint Peter according to Catholic tradition. He was notable for convoking the First Vatican Council in 1868 which defined the dogma of papal infallibility before taking a break in summer of 1870. The council never reconvened. At the same time, France started the French-Prussian War and removed the troops that protected the Papal States, which allowed the Capture of Rome by the Kingdom of Italy on 20 September 1870. Thereafter, he refused to leave Vatican City, declaring himself a "prisoner in the Vatican".

At the time of his election, he was a liberal reformer, and during his early papacy, he enacted progressive reforms, but his approach changed after the Revolutions of 1848. When his prime minister, Pellegrino Rossi, was assassinated and Pius himself was made prisoner in his own palace, he fled Rome and excommunicated all participants in the short-lived Roman Republic. After its suppression by the French army and his return in 1850, his policies and doctrinal pronouncements became increasingly conservative. He was responsible for the kidnapping of Edgardo Mortara, a six-year-old taken by force from his Jewish family who went on to become a Catholic priest in his own right and unsuccessfully attempted to convert his Jewish parents.

The First Ecumenical Council of the Vatican, commonly known as the First Vatican Council or Vatican I, was the 20th ecumenical council of the Catholic Church, held three centuries after the preceding Council of Trent which was adjourned in 1563. The council was convoked by Pope Pius IX on 29 June 1868, under the rising threat of the Kingdom of Italy encroaching on the Papal States. It opened on 8 December 1869 and was adjourned on 20 September 1870 after the Italian Capture of Rome. Its best-known decision is its definition of papal infallibility.

The council's main purpose was to clarify Catholic doctrine in response to the rising influence of the modern philosophical trends of the 19th century. In the Dogmatic Constitution on the Catholic Faith (Dei Filius), the council condemned what it considered the errors of rationalism, anarchism, communism, socialism, liberalism, materialism, modernism, naturalism, pantheism, and secularism.

Conciliarism was a movement in the 14th-, 15th- and 16th-century Catholic Church which held that supreme authority in the Church resided with an ecumenical council, apart from, despite, or even if opposed by, the pope.

The movement emerged in response to the Western Schism between rival popes in Rome and Avignon. It was proposed that both popes abdicate in order to allow a new election that implemented a proposal where government supporters of the popes withdraw allegiance and thus prepare the way for a new election. The schism led to the summoning of the Council of Pisa (1409), which failed to end the schism, and the Council of Constance (1414–1418), which had more success, but which also proclaimed its own superiority over the Pope. Conciliarism reached its apex with the Council of Basel (1431–1449). The eventual victor in the warring movements was the pope and the institution of the papacy: the pope's power and teaching authority was confirmed by the condemnation of conciliarism at the Fifth Lateran Council (1512–1517). The apex of the theory of papal authority, on the other hand, was probably reached with the adoption of the doctrine of papal infallibility, promulgated (ironically) by the First Vatican Council (1870).