With a membership currently estimated at over 85 million members worldwide, the Anglican Communion is the third largest Christian communion in the world, after the Roman Catholic Church and the Eastern Orthodox Churches.

In the Eastern Orthodox and Eastern Catholic Churches, the Abbot is referred to as the Hegumen.

Arianism is defined as those teachings attributed to Arius which are in opposition to mainstream Trinitarian Christological doctrine, as determined by the first two Ecumenical Councils and currently maintained by the Roman Catholic Church, the Eastern Orthodox Churches, the Oriental Orthodox Churches, and most Reformation Protestant Churches.

In the Catholic Church ( both the Latin Rite and Eastern Catholic ), Eastern Orthodox, Coptic and Anglican abbeys, the mode of election, position, rights, and authority of an abbess correspond generally with those of an abbot.

Saint Alcuin ( Alcuin of York ) is considered as a saint by all the main branches of Christianity: Roman Catholic, Anglican and Eastern Orthodox Churches.

*** Feast of the Dormition of the Theotokos ( Eastern Orthodox, Oriental Orthodox and Eastern Catholic Churches )

** Leave-Taking of the Feast of the Dormition of the Theotokos ( Eastern Catholic Churches )

Further, proponents of the necessity of the personal apostolic succession of bishops within the Church point to the universal practice of the undivided early Church ( up to AD 431 ), before being divided into the Church of the East, Oriental Orthodoxy, the Eastern Orthodox Church and the Roman Catholic Church.

Churches that claim some form of episcopal apostolic succession, dating back to the apostles or to leaders from the apostolic era, include the Roman Catholic Church, the Eastern Orthodox and Oriental Orthodox Churches, the Church of the East, the Anglican Communion, and some Lutheran Churches ( see below ).

Roman Catholics recognize the validity of the apostolic successions of the bishops, and therefore the rest of the clergy, of the Eastern Orthodox, Oriental Orthodox, Church of the East, and the Old Catholic Church ( Union of Utrecht only ).

The Eastern Orthodox generally recognize Roman Catholic orders, but have a different concept of the apostolic succession as it exists outside of Eastern Orthodoxy.

Like the Roman Catholic Church, these ancient Eastern churches may use the doctrine of apostolic succession in ministry in their apologetics against Protestantism.

The Roman Catholic, Eastern Orthodox and Coptic and Old Catholic Churches consider this anointing to be a sacrament.

Liturgical rites of the Catholic Church, both Western and Eastern, other than the Roman, have a variety of other forms for celebrating the sacrament.

The teaching of the Eastern Orthodox Church on the Holy Mystery ( sacrament ) of Unction is similar to that of the Roman Catholic Church.

Athanasius is counted as one of the four Great Doctors of the Church in the Roman Catholic Church as well as one of the Great Doctors of the Church in Eastern Orthodoxy, where he is also labeled the " Father of Orthodoxy ".

He is venerated by the Roman Catholic Church, Oriental and Eastern Orthodox churches, the Lutherans, and the Anglican Communion.

* Eastern Catholic Church

With the exception of the Roman Catholic and the Orthodox Catholic Churches, most churches make no moral distinction between rhythm and mechanical or chemical contraceptives, allowing the couple free choice.

Today, the Roman Catholic and Orthodox Churches stand virtually alone in holding that conviction.

Its intent was to provide the basis for discussions of reunion with the Roman Catholic and Orthodox Churches, but it had the ancillary effect of establishing parameters of Anglican identity.

* 1962 – Representatives from the Russian Orthodox Church and Vatican City meet in Metz, France, and come to an agreement wherein the Russian church would send observers to the Second Vatican Council and in exchange, the Roman Catholic Church would refuse to condemn Communism.

As they do not receive Holy Orders in the Catholic, Orthodox and Oriental Churches, they do not possess the ability to ordain any religious to Holy Orders, or even admit their members to the non-ordained ministries to which they can be installed by the ordained clergy ( females do not serve as clergy anyway, per formal church teaching, in these churches ), nor do they exercise the authority they do possess under canon law over any territories outside of their monastery and its territory ( though non-cloistered, non-contemplative female religious members who are based in a convent or monastery but who participate in external affairs may assist as needed by the diocesan bishop and local secular clergy and laity, in certain pastoral ministries and administrative and non-administrative functions not requiring ordained ministry or status as a male cleric in those churches or programs ).

Surviving medieval art is primarily religious in focus and funded largely by the State, Roman Catholic or Orthodox church, powerful ecclesiastical individuals, or wealthy secular patrons.

The lack of apostolic succession through bishops is the primary basis on which Protestant communities are not considered churches by the Orthodox churches and the Roman Catholic Church.

The Eastern Orthodox, Oriental Orthodox and Eastern Catholic churches may have minor differences in their lists of accepted books.

Within the Catholic Church, Eastern Orthodox, Oriental Orthodox, Anglican, Old Catholic, Independent Catholic Churches, and in the Assyrian Church of the East, bishops claim apostolic succession, a direct historical lineage dating back to the original Twelve Apostles.

Bishops form the leadership in the Roman Catholic Church, the Eastern Orthodox Church, the Oriental Orthodox Churches, the Anglican Communion, the Lutheran Church, the Independent Catholic Churches, the Independent Anglican Churches, and certain other, smaller, denominations.

; Catholicos: Catholicoi are the heads of some of the Eastern Orthodox, Oriental Orthodox, and Eastern Rite Catholic sui iuris churches ( notably the Armenian ), roughly similar to a Patriarch ( see above ).

However, in the Byzantine and other Eastern rites, whether Eastern or Oriental Orthodox or Eastern Catholic, chrismation is done immediately after baptism, and thus the priest is the one who confirms, using chrism blessed by a bishop.

The Catholic Church does recognise as valid ( though illicit ) ordinations done by breakaway Catholic, Old Catholic or Oriental bishops, and groups descended from them ; it also regards as both valid and licit those ordinations done by bishops of the Eastern churches, so long as those receiving the ordination conform to other canonical requirements ( for example, is an adult male ) and an orthodox rite of episcopal ordination, expressing the proper functions and sacramental status of a bishop, is used ; this has given rise to the phenomenon of episcopi vagantes ( for example, clergy of the Independent Catholic groups which claim apostolic succession, though this claim is rejected by both Orthodoxy and Catholicism ).

There is a mutual recognition of the validity of orders amongst Roman Catholic, Eastern Orthodox, Old Catholic, Oriental Orthodox and Assyrian Nestorian churches.

In the Catholic, Orthodox and Oriental Orthodox traditions, bishops are required to be celibate.

A cathedral is a church, usually Roman Catholic, Anglican, Oriental Orthodox or Eastern Orthodox, housing the seat of a bishop.

It is the internal ecclesiastical law governing the Catholic Church ( both Latin Rite and Eastern Catholic Churches ), the Eastern and Oriental Orthodox churches, and the Anglican Communion of churches.

A Catholic priest recently recounted how in the chapel of a large city university, following Anglican evensong, at which there was a congregation of twelve, he celebrated Mass before more than a hundred.

There was so much interest shown in this present-day venture that it was continued on B.B.C., where comments were equally made by an Anglican parson, a Free Church minister and a Catholic priest.

A notable example of this was the discussion of Christian unity by the Catholic Archbishop of Liverpool, Dr. Heenan, and the Anglican Archbishop of York, Dr. Ramsey, recently appointed Archbishop of Canterbury.

The Anglican Communion considers itself to be part of the One, Holy, Catholic and Apostolic Church and to be both Catholic and Reformed.

Also shown are the churches in full communion with the Anglican Communion: the Nordic Lutheran churches of the Porvoo Communion ( Green ) and the Old Catholic Church | Old Catholic churches of the Utrecht Union ( Red ).

In addition to other member churches, the churches of the Anglican Communion are in full communion with the Old Catholic churches of the Union of Utrecht and the Scandinavian Lutheran churches of the Porvoo Communion in Europe, the India-based Mar Thoma and Malabar Independent Syrian churches and the Philippine Independent Church, also known as the Aglipayan Church.

The Roman Catholic Church does not recognise most Anglican orders ( see Apostolicae Curae ).

In Western Christianity, this day is observed principally in the Catholic Church, although some churches of Anglican Communion and the Old Catholic Churches also celebrate it.

The Nicene Creed and the shorter Apostles ' Creed are articles, or professions of Faith said by members of the Roman Catholic Church and the Anglican Communion.

His father was a shipping merchant who was brought up as a Catholic but had Protestant sympathies, and his mother was a devout Independent unaffiliated with the Anglican Church.

** Endelienta ( Roman Catholic and Anglican Church )

** Bartholomew ( Roman Catholic, Anglican )

In the Catholic Church and the Anglican Communion, he is a saint and pre-eminent Doctor of the Church, and the patron of the Augustinians ; his memorial is celebrated 28 August, the day of his death.

They also point to the fact that the monarch must swear to defend the faith and be a member of the Anglican Communion, but that a Roman Catholic monarch would, like all Roman Catholics, owe allegiance to the Pope.

" He further asserts that because the Roman Catholic Church does not recognise the Church of England as an apostolic church, a Roman Catholic monarch who abided by their faith's doctrine would be obliged to view Anglican and Church of Scotland archbishops, bishops, and clergy as part of the laity and therefore " lacking the ordained authority to preach and celebrate the sacraments.