
Defining Christian Traditions
Catholic
The Catholic Church includes the international body of churches in full communion with the bishop of
Rome, the pope. These churches include the Western (or Latin) church and 22 Eastern Catholic churches.1 Each of these churches has a distinct hierarchy and traditional liturgy, prayers and religious observances.
The Western (Latin) church is the largest of these autonomous churches. Among the major branches of the
Eastern churches are the Alexandrian, Antiochene, Armenian, Byzantine and Chaldean.2
Catholicism, taken as a whole, is the world’s largest Christian tradition. The Catholic Church teaches that
its bishops are the successors of Christ’s apostles and that the pope, as the successor to St. Peter, possesses
a unique authority in the church.3 Catholic doctrine maintains that the church is infallible in its
dogmatic teaching on matters of faith and morals.4 Catholic worship is centered on the Eucharist, in which,
according to the church’s teaching, the bread and wine are supernaturally transformed into the body and
blood of Christ. 5
Estimates for the number of Catholics in this report also include members of some relatively small Catholic
groups (such as the Brazilian Catholic Apostolic Church) that are not in communion with the bishop of Rome.
Protestant
Protestants are broadly defined in this report to include three groups.6 The first group is made up of
historic Protestants who belong to churches originating (or reformulated) at the time of the 16th-century
Protestant Reformation in Europe, as well as other denominations that came later, such as Methodists.
The Protestant Reformation was led by Martin Luther, John Calvin and other theologians who “protested”
the doctrines, rituals and ecclesiastical structure of the Catholic Church, leading to the creation of new
national churches. The doctrines of the various Protestant denominations vary, but most include belief in
grace through faith alone (known as sola fide or “by faith alone”), belief in the Bible as the ultimate
authority in matters of faith and order (known as sola scriptura or “by scripture alone”) and belief in the priesthood of all believers.7
Anglicans are the second group of Christians categorized in this report under the broad banner of Protestantism.
This category refers to Christians who belong to churches with historical connections to the Church
of England or have similar beliefs, worship styles and church structures. The great majority of Anglicans
are members of churches that are part of the international Anglican Communion, which recognizes the
archbishop of Canterbury as its “Focus for Unity.”8 The Church of England emerged as a distinct Western
Christian ecclesial tradition in the early 16th century, when King Henry VIII declared his supremacy over
the English church and its independence from papal authority.9
The third group broadly defined as Protestants in this report is independent Christians. Independent
Christians have developed ecclesial structures, beliefs and practices that are claimed to be independent of
historic, organized Christianity.10 Independent Christians include denominations in sub-Saharan Africa that
identify as independent from historically Protestant denominations, churches in China that are not affiliated
with official religious associations and nondenominational churches in the United States.
Orthodox Christian
Orthodox Christians are members of self-governing churches that belong to the Eastern Christian tradition.
In 1054, the Great Schism divided the Christian church into an Eastern, Greek church centered in Constantinople
(Istanbul today) and a Western, Latin church centered in Rome. This formalized a cleavage that had
been growing for centuries. A major source of division was that the Eastern church did not recognize the
bishop of Rome’s claimed jurisdiction over the entire church. The Eastern insistence on ecclesial autonomy
persists: Orthodox Christianity is organized into “autocephalous” churches, each under the leadership of its
own supreme patriarch.
Orthodox Christianity has two main branches: Eastern Orthodox churches and Oriental Orthodox churches.
There are more than a dozen autocephalous Eastern Orthodox churches, including the Ecumenical Patriarchate
of Constantinople, the Patriarchate of Antioch, the Greek Orthodox Church, the Russian Orthodox
Church, the Romanian Orthodox Church, the Serbian Orthodox Church and the Ukrainian Orthodox
Church.11 Though they are under no common hierarchical authority, the Eastern Orthodox churches enjoy
full communion with each other. The head of the Ecumenical Patriarchate of Constantinople is recognized
by all Eastern Orthodox churches as the “Ecumenical Patriarch” who enjoys primacy of honor as well as unique authority to convene pan-Orthodox synods and promote Orthodox unity.12
Oriental Orthodox churches are those Eastern Orthodox churches that recognize only the first three
ecumenical councils convened by the church’s bishops to discuss and determine matters of church doctrine
and discipline — the First Council of Nicaea, the First Council of Constantinople and the First Council of
Ephesus.13 Unlike the Eastern Orthodox Church, which embraces the Council of Chalcedon’s teaching that
Christ has two natures, divine and human, Oriental Orthodox churches hold that Christ has one indivisible
nature. The Oriental Orthodox churches are therefore also called non-Chalcedonian churches. The Oriental
Orthodox churches include the Coptic Orthodox Church, Ethiopian Orthodox Church, Eritrean Orthodox
Church, Syriac Orthodox Church, Malankara Orthodox Syrian Church (India) and Armenian Apostolic
Church.14
Other Christian Traditions
Members of other Christian groups self-identify as Christian although older Christian traditions may view
them as distinct from mainstream Christianity. Many of these groups – including the Church of Jesus Christ
of Latter-day Saints (Mormons), Jehovah’s Witnesses and the Christian Science Church – originated in the
United States. These groups often depart from traditional Christian beliefs with respect to the trinitarian
nature of God and have additional sacred texts beyond the Christian Bible and/or their own authoritative
interpretations of the Bible. For example, the canon of the Mormon church includes four texts: the Bible
(both Old and New Testaments), the Book of Mormon, the Doctrine and Covenants and the Pearl of Great
Price. Jehovah’s Witnesses believe that “Christ is God’s Son and is inferior to Him” as well as that the
destruction of the present world system at Armageddon is imminent.15 They prefer their own Bible translation,
the New World Translation of the Holy Scriptures.16 Christian Science was founded by Mary Baker
Eddy (1821-1910). Her 1875 book, Science and Health with Key to the Scriptures, is one of its central
texts, along with the Bible.17 Other groups in this category include the Unification Church, Swedenborgians
and Christadelphians.
Footnotes:
1 “Methodology,” in David B. Barrett, editor, World Christian Encyclopedia: A Comparative Study of Churches and Religions
in the Modern World, AD 1900-2000, Oxford University Press, 1982, page 80. (return to text)
2 “Eastern Rites,” in J. D. Douglas, Walter A. Elwell and Peter Toon, The Concise Dictionary of the Christian Tradition: Doctrine,
Liturgy, History, Regency Reference Library, 1989, page 135. (return to text)
3 “Apostles,” in Honoré Coppieters, The Catholic Encyclopedia, Volume 1, Robert Appleton Company, 1907; “The Pope,” in George Joyce, The Catholic Encyclopedia, Volume 12, Robert Appleton
Company, 1911. (return to text)
4 “Faith,” in Hugh Pope, The Catholic Encyclopedia, Volume 5, Robert Appleton Company, 1909; “Morality,” in George Joyce, The Catholic Encyclopedia, Volume 10, Robert Appleton Company,
1911. (return to text)
5 “Roman Catholicism,” in J. D. Douglas, Walter A. Elwell and Peter Toon, The Concise Dictionary of the Christian Tradition:
Doctrine, Liturgy, History, Regency Reference Library, 1989, page 330; “Orthodox and Oriental Orthodox Churches,” in
New Catholic Encyclopedia, Volume 14, Gale, 2002, page 158. (return to text)
6 Some information about the estimated distribution of Protestants among these subgroups is provided in the section on
Christian Movements and Denominations. (return to text)
7 “Protestantism,” in J. D. Douglas, Walter A. Elwell and Peter Toon, The Concise Dictionary of the Christian Tradition:
Doctrine, Liturgy, History, Regency Reference Library, 1989, page 309; F. L. Cross, The Oxford Dictionary of the Christian
Church, Oxford University Press, 1957, pages 1116-1117; John Bowker, editor, The Oxford Dictionary of World Religions,
Oxford University Press, 1997, pages 771-772. (return to text)
8 Anglican Communion Office.(return to text)
9 “Protestantism: Anglican Communion,” in The New Encyclopaedia Britannica, Volume 26, Encyclopaedia Britannica, Inc.,
2007, page 246. (return to text)
10 “Independents,” in Todd M. Johnson and Kenneth R. Ross, editors, Atlas of Global Christianity, Edinburgh University
Press, 2009, pages 76-77. (return to text)
11 Some of the autocephalous churches are headed by “patriarchs” while the others are headed by archbishops or metropolitans.
See “Eastern Orthodoxy,” in The New Encyclopaedia Britannica, Volume 17, Encyclopaedia Britannica, Inc., 2007,
page 838. (return to text)
12 “Eastern Orthodox Church,” in J. D. Douglas, Walter A. Elwell and Peter Toon, The Concise Dictionary of the Christian
Tradition: Doctrine, Liturgy, History, Regency Reference Library, 1989, pages 134-135; “Orthodox and Oriental Orthodox
Churches,” in New Catholic Encyclopedia, Volume 10, Gale, 2002, pages 679-681; “Eastern Orthodoxy,” in The New
Encyclopaedia Britannica, Volume 17, Encyclopaedia Britannica, Inc., 2007, page 838. (return to text)
13 An ecumenical or general council is a meeting of all of the church’s bishops to discuss and determine matters of church
doctrine and discipline. Many councils were convened to address specific theological disputes. For example, the First
Council of Nicaea was convened in 325 to resolve disagreements concerning the relationship between Christ and God the
Father; the First Council of Constantinople was convened in 381 to ratify the work of the Council of Nicaea and definitively
end ongoing controversy concerning the relationship between Christ and the Father; and the First Council of Ephesus
was convened in 431 to resolve emerging disagreement concerning the nature of Christ and the relationship between his
humanity and divinity. The Council of Chalcedon was convened in 451 to resolve disagreements concerning the nature of
Christ. (See “Arius, Arianism” in David W. Bercot, editor, A Dictionary of Early Christian Beliefs: A Reference Guide to More
Than 700 Topics Discussed by the Early Church Fathers, Hendrickson Publishers, 1998, pages 35-36; John Bowker, editor,
The Oxford Dictionary of World Religions, Oxford University Press, 1997, pages 235, 241-242, 316, 692). (return to text)
14 “Orthodox and Oriental Orthodox Churches,” in New Catholic Encyclopedia, Volume 10, Gale, 2002, page 681.
The Syrian Orthodox Church changed its name to the Syriac Orthodox Church in 2000. See Atlas of Global Christianity,
Edinburgh University Press, 2009, page 84. (return to text)
15 Watchtower, Official Web Site of Jehovah’s Witnesses, http://www.watchtower.org/e/jt/article_03.htm and http://www.
watchtower.org/e/dg/article_09.htm. (return to text)
16 Watchtower, Official Web Site of Jehovah’s Witnesses. (return to text)
17 ChristianScience.com, owned and operated by The First Church of Christ, Scientist, and its affiliate, The Christian
Science Publishing Society. (return to text)