In Western philosophy, the spread of Christianity through the Roman Empire marked the ending of Hellenistic philosophy and ushered in the beginnings of Medieval philosophy, whereas in Eastern philosophy, the spread of Islam through the Arab Empire marked the end of Old Iranian philosophy and ushered in the beginnings of early Islamic philosophy.

Ousia is essence or being, in Eastern Christianity, and is the aspect of God that is completely incomprehensible to mankind and human perception.

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

While the Society was oriented toward an Eastern and especially Indian approach, Steiner was trying to develop a path that embraced Christianity and natural science.

Athanasius is venerated as a Christian saint, whose feast day is 2 May in Western Christianity, 15 May in the Coptic Orthodox Church, and 18 January in the other Eastern Orthodox Churches.

His other important works include his Letters to Serapion, which dealt with the divinity of the Holy Spirit, and his classic Life of St Anthony, which was translated into several languages and played an important role in the spreading of the ascetic ideal in Eastern and Western Christianity.

Other vestments and insignia vary between Eastern and Western Christianity.

* Holy water in Eastern Christianity

Saint Bruno of Querfurt ( c. 974 – February 14, 1009 ), also known as Brun and Boniface, is a sainted missionary bishop and martyr, who was beheaded near the border of Kievan Rus and Lithuania while trying to spread Christianity in Eastern Europe.

Worldwide the three largest groups of Christianity are the Roman Catholic Church, the Eastern Orthodox Church, and the various denominations of Protestantism.

An Eastern Christianity | Eastern Christian Icon depicting Constantine I and Christianity | Emperor Constantine and the Fathers of the First Council of Nicaea ( 325 ) as holding the Niceno – Constantinopolitan Creed of 381.

The three primary divisions of Christianity are Catholicism, Eastern Orthodoxy, and Protestantism.

Another distinction that is sometimes drawn is between Eastern Christianity and Western Christianity.

Like the Roman Catholic Church, the Eastern Orthodox Church also traces its heritage to the foundation of Christianity through Apostolic succession and has an episcopal structure, though the autonomy of the individual, mostly national churches is emphasized.

Eastern Orthodoxy is the second largest single denomination in Christianity, with over 200 million adherents.

Eastern Orthodox Christianity does not officially condemn or endorse capital punishment.

Clement is regarded as a Church Father, and he is venerated as a saint in Orthodox Christianity, Eastern Catholicism and Anglicanism.

Like many of the Eastern Fathers, he has an essentially moralistic conception of Christianity.

Some Christian denominations hold that salvation depends upon transformational faith in Jesus, which expresses itself in good works as a testament ( or witness ) to ones faith for others to see ( primarily Eastern Orthodox Christianity and Roman Catholicism ), while others ( including most Protestants ) hold that faith alone is necessary for salvation.

Eastern Orthodox Christianity emphasizes a continuing life of repentance or metanoia, which includes an increasing improvement in thought, belief and action.

Deuterocanonical books is a term used since the sixteenth century in the Catholic Church and Eastern Christianity to describe certain books and passages of the Christian Old Testament that are not part of the Hebrew Bible.

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.

Some Eastern Orthodox Churches have issued statements to the effect that Anglican orders could be accepted, yet have still reordained former Anglican clergy ; other Orthodox churches have rejected Anglican orders altogether.

** April 6 ( Eastern Orthodox liturgics )

** April 15 ( Eastern Orthodox liturgics )

** April 30 ( Eastern Orthodox liturgics )

** August 22 ( Eastern Orthodox liturgics )

** August 6 ( Eastern Orthodox liturgics )

** August 9 ( Eastern Orthodox liturgics )

The Eastern Orthodox Church observes several All Souls ' Days during the year.

The Eastern Orthodox Church dedicates several days throughout the year to the dead, mostly on Saturdays, because of Jesus ' resting in the Holy Sepulchre on that day.

** August 13 ( Eastern Orthodox liturgics )

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

** August 2 ( Eastern Orthodox liturgics )

** April 1 ( Eastern Orthodox liturgics )

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.

** August 1 ( Eastern Orthodox liturgics )

** August 3 ( Eastern Orthodox liturgics )

** April 26 ( Eastern Orthodox liturgics )

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.

** August 8 ( Eastern Orthodox liturgics )

** April 16 ( Eastern Orthodox liturgics )