Statement of belief adopted at the First Ecumenical Council in 325
The Nicene Creed (/ˈnaɪsiːn/; Koinē Greek: Σύμβολον τῆς Νικαίας, romanized: Sýmvolon tis Nikéas), also called the Creed of Constantinople,[1] is the defining statement of belief of mainstream Christianity[2][3] and in those Christian denominations that adhere to it. The original Nicene Creed was first adopted at the First Council of Nicaea in 325. According to a popular view forwarded by the Council of Chalcedon of 451, the Creed was amended in 381 by the First Council of Constantinople as "consonant to the holy and great Synod of Nice."[4] However, there are some who comment on these ancient Councils who say "there is a failure of evidence" for this position since no one between the years of 381–451 thought of it in this light.[5] Nonetheless, the amended form is presently referred to as the Nicene Creed or the Niceno-Constantinopolitan Creed.
The Nicene Creed is part of the profession of faith required of those undertaking important functions within the Orthodox and Catholic[6][7] Churches. Nicene Christianity regards Jesus as divine and "begotten of the Father".[8] Various conflicting theological views existed before the fourth century and these spurred the ecumenical councils which eventually developed the Nicene Creed, and various non-Nicene beliefs have emerged and re-emerged since the fourth century, all of which are considered heresies[9] by adherents of Nicene Christianity.
^Cone, Steven D.; Rea, Robert F. (2019). A Global Church History: The Great Tradition through Cultures, Continents and Centuries. Bloomsbury Publishing. pp. lxxx. ISBN978-0-567-67305-3.
^World Encyclopaedia of Interfaith Studies: World religions. Jnanada Prakashan. 2009. ISBN978-81-7139-280-3. In the most common sense, "mainstream" refers to Nicene Christianity, or rather the traditions which continue to claim adherence to the Nicene Creed.