Early ChristianityEarly Christianity, or Paleochristianity, describes the historical era of the Christian religion up to the First Council of Nicaea in 325. Christianity spread from the Levant, across the Roman Empire, and beyond. Originally, this progression was closely connected to already established Jewish centers in the Holy Land and the Jewish diaspora. The first followers of Christianity were Jews who had converted to the faith, i.e. Jewish Christians. Early Christianity contains the Apostolic age and is followed by, and substantially overlaps with, the Patristic era.
Council of HieriaThe iconoclast Council of Hieria was a Christian council of 754 which viewed itself as ecumenical, but was later rejected by the Second Council of Nicaea (787) and by Catholic and Orthodox churches, since none of the five major patriarchs were represented in Hieria. However it is preferred over Second Nicea by some Protestants. The Council of Hieria was summoned by the Byzantine Emperor Constantine V in 754 in the palace of Hieria at Chalcedon.
Church FathersThe Church Fathers, Early Church Fathers, Christian Fathers, or Fathers of the Church were ancient and influential Christian theologians and writers who established the intellectual and doctrinal foundations of Christianity. The historical period in which they worked became known as the Patristic Era and spans approximately from the late 1st to mid-8th centuries, flourishing in particular during the 4th and 5th centuries, when Christianity was in the process of establishing itself as the state church of the Roman Empire.
Christian theologyChristian theology is the theology of Christian belief and practice. Such study concentrates primarily upon the texts of the Old Testament and of the New Testament, as well as on Christian tradition. Christian theologians use biblical exegesis, rational analysis and argument.
Byzantine EmpireThe Byzantine Empire, also referred to as the Eastern Roman Empire, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinople. It survived the fall of the Western Roman Empire in the 5th century AD and continued to exist until the fall of Constantinople to the Ottoman Empire in 1453. During most of its existence, the empire remained the most powerful economic, cultural, and military force in the Mediterranean world.
Church of the EastThe Church of the East ( ʿĒḏtā d-Maḏenḥā) or the East Syriac Church, also called the Church of Seleucia-Ctesiphon, the Persian Church, the Assyrian Church, the Babylonian Church or the Nestorian Church, was an Eastern Christian church of the East Syriac Rite, based in Mesopotamia. It was one of three major branches of Eastern Christianity that arose from the Christological controversies of the 5th and 6th centuries, alongside the Oriental Orthodox Churches and the Chalcedonian Church.
Constantine the Great and ChristianityDuring the reign of the Roman Emperor Constantine the Great (306–337 AD), Christianity began to transition to the dominant religion of the Roman Empire. Historians remain uncertain about Constantine's reasons for favoring Christianity, and theologians and historians have often argued about which form of early Christianity he subscribed to. There is no consensus among scholars as to whether he adopted his mother Helena's Christianity in his youth, or, as claimed by Eusebius of Caesarea, encouraged her to convert to the faith he had adopted.
Biblical canonA biblical canon is a set of texts (also called "books") which a particular Jewish or Christian religious community regards as part of the Bible. The English word canon comes from the Greek κανών kanōn, meaning "rule" or "measuring stick". The use of the word "canon" to refer to a set of religious scriptures was first used by David Ruhnken, in the 18th century. Various biblical canons have developed through debate and agreement on the part of the religious authorities of their respective faiths and denominations.
ConsubstantialityConsubstantiality, a term derived from consubstantialitas, denotes identity of substance or essence in spite of difference in aspect. It appears most commonly in its adjectival form, "consubstantial", from Latin consubstantialis, and its best-known use is in regard to an account, in Christian theology, of the relation between Jesus Christ and God the Father. The affirmation that Jesus Christ is "consubstantial with the Father" appears in the Nicene Creed. Greek was the language in which the Nicene Creed was originally enunciated.
AriusArius (əˈraɪəs,_ˈɛəri-; Ἄρειος, Áreios; 250 or 256 – 336) was a Cyrenaic presbyter, ascetic, and priest associated with the doctrine of Arianism. His teachings about the nature of the Godhead in Christianity, which emphasized God the Father's uniqueness and Christ's subordination under the Father, and his opposition to what would become the dominant Christology (Homoousian Christology) made him a primary topic of the First Council of Nicaea convened by Emperor Constantine the Great in 325.