Catholic ChurchThe Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with 1.3 billion baptized Catholics worldwide It is among the world's oldest and largest international institutions, and has played a prominent role in the history and development of Western civilization. The church consists of 24 sui iuris churches, including the Latin Church and 23 Eastern Catholic Churches, which comprise almost 3,500 dioceses and eparchies located around the world.
Eusebius of NicomediaEusebius of Nicomedia (juːˈsiːbiəs; Εὐσέβιος; died 341) was an Arian priest who baptized Constantine the Great on his deathbed in 337. A fifth-century legend evolved that Pope Sylvester I was the one to baptize Constantine, but this is dismissed by scholars as a forgery 'to amend the historical memory of the Arian baptism that the emperor received at the end of his life, and instead to attribute an unequivocally orthodox baptism to him.' He was a bishop of Berytus (modern-day Beirut) in Phoenicia.
Nicene CreedThe Nicene Creed (ˈnaɪsiːn; Sýmvolon tis Nikéas) is the defining statement of belief of Nicene or mainstream Christianity and in those Christian denominations that adhere to it. The original Nicene Creed was first adopted at the First Council of Nicaea in 325. In 381, it was amended at the First Council of Constantinople. The amended form is also referred to as the Nicene Creed, or the Niceno-Constantinopolitan Creed for disambiguation.
TrinityThe Christian doctrine of the Trinity (Trinitas, from trinus 'threefold') is the central doctrine concerning the nature of God in most Christian churches, which defines one God existing in three , , consubstantial divine persons: God the Father, God the Son (Jesus Christ) and God the Holy Spirit, three distinct persons (hypostases) sharing one essence/substance/nature (homoousion) As the Fourth Lateran Council declared, it is the Father who s, the Son who is , and the Holy Spirit who proceeds.
PopeThe pope (papa, from πάππας), also known as the supreme pontiff (pontifex maximus or summus pontifex), Roman pontiff (Romanus pontifex) or sovereign pontiff, is the bishop of Rome (or historically the patriarch of Rome), head of the worldwide Catholic Church, and has also served as the head of state or sovereign of the Papal States and later the Vatican City State since the eighth century.
First Council of NicaeaThe First Council of Nicaea (naɪˈsi:ə ; Sýnodos tês Nīkaíās) was a council of Christian bishops convened in the Bithynian city of Nicaea (now İznik, Turkey) by the Roman Emperor Constantine I in AD 325. This ecumenical council was the first effort to attain consensus in the church through an assembly representing all Christendom. Hosius of Corduba may have presided over its deliberations.
Eastern OrthodoxyEastern Orthodoxy, otherwise known as Eastern Orthodox Christianity or Byzantine Christianity, is one of the three main branches of Chalcedonian Christianity, alongside Roman Catholicism and Protestantism. Like the Pentarchy of the first millennium, the mainstream (or "canonical") Eastern Orthodox Church is organised into autocephalous churches independent from each other. In the 21st century, the number of mainstream autocephalous churches is seventeen; there also exist autocephalous churches unrecognized by those mainstream ones.
ProtestantismProtestantism is a branch of Christianity that follows the theological tenets of the Protestant Reformation, a movement that began in the 16th century with the goal of reforming the Catholic Church from perceived errors, abuses, and discrepancies. Protestantism emphasizes the Christian believer's justification by God in faith alone (sola fide) rather than by a combination of faith with good works as in Catholicism; the teaching that salvation comes by divine grace or "unmerited favor" only (sola gratia); the priesthood of all believers in the Church; and the sola scriptura ("scripture alone") that posits the Bible as the sole infallible source of authority for Christian faith and practice.
Chalcedonian DefinitionThe Chalcedonian Definition (also called the Chalcedonian Creed or the Definition of Chalcedon) is a declaration of Christ's nature (that it is dyophysite), adopted at the Council of Chalcedon in AD 451. Chalcedon was an early centre of Christianity located in Asia Minor. The council was the fourth of the ecumenical councils that are accepted by Chalcedonian churches which include the Catholic, Eastern Orthodox, Lutheran, Anglican and Reformed churches.
ArianismArianism (Ἀρειανισμός, Areianismós) is a Christological doctrine first attributed to Arius (AD 256–336), a Christian presbyter from Alexandria, Egypt. Arian theology holds that Jesus Christ is the Son of God, who was begotten by God the Father with the difference that the Son of God did not always exist but was begotten/made before "time" by God the Father; therefore, Jesus was not coeternal with God the Father, but nonetheless Jesus began to exist outside time as time applies only to the creations of God.