Christianity in Iran dates back to the early years of the religion during the time of Jesus, predating Islam. The Christian faith has always comprised a minority in Iran under its previous state religions; initially Zoroastrianism in historical Persia, followed by Sunni Islam in the Middle Ages after the Arab conquest, and Shia Islam since the Safavid conversion of the 15th century; although it had a much larger representation in the past than it does today. Iranian Christians have played a significant part in the historical Christian mission: currently, there are at least 6000 churches and 100,000–150,000 Christians in Iran.
Major denominations
A number of Christian denominations are represented in Iran. Many members of the larger and older churches belong to minority ethnic groups, with the Armenians and Assyrians having their own distinctive culture and language. The members of the newer and smaller churches are drawn both from the traditionally Christian ethnic minorities and converts from a non-Christian background.
The main Christian churches in Iran are:
Armenian Apostolic Church (between 110,000, 250,000, and 300,000 adherents) Assyrian Church of the East (about 11,000–20,000 adherents), Catholic Church (about 21,380 adherents) in three different rites. Chaldean Catholic Church (3,900 adherents as of 2014) Armenian Catholic Church and Latin Church Other particularities and churches include: Presbyterianism, including the Assyrian Evangelical Church Pentecostalism, including the Assyrian Pentecostal Church Jamaʿat-e Rabbani (Iranian Assemblies of God) Anglican Diocese of Iran According to Operation World, there are between 7,000 and 15,000 members and adherents of the various Protestant, Evangelical, and other minority Christian denominations in Iran, though these numbers are particularly difficult to verify under the current political circumstances.
In the 2016 census, the Statistical Center of Iran reported there were 117,700 Christians in the country; other reports put the figure at over half a million people.
The "Country Information and Guidance: Christians and Christian Converts, Iran" report published in December 2014 by the U.K. Home Office states that there were 370,000 Christians in Iran.
History
According to the Acts of the Apostles there were Persians, Parthians and Medes among the first new Christian converts at Pentecost. Since then there has been a continuous presence of Christians in Iran.
During the apostolic age Christianity began to establish itself throughout the Mediterranean. However, a quite different Semitic-speaking Christian culture developed on the eastern borders of the Roman Empire and in Persia. Syriac Christianity owed much to preexistent Jewish communities and to the Aramaic language. This language had been spoken by Jesus, and, in various modern Eastern Aramaic forms is still spoken by the ethnic Assyrian Christians in Iran, northeast Syria, southeast Turkey and Iraq today (see Assyrian Neo-Aramaic, and Senaya language).
From Persian-ruled Assyria (Assuristan), missionary activity spread Eastern-Rite Syriac Christianity throughout Assyria and Mesopotamia, and from there into Persia, Asia Minor, Syria, the Caucasus and Central Asia, establishing the Saint Thomas Christians of India and erecting the Nestorian Stele and the Daqin Pagoda in China.
Early Christian communities straddling the Roman-Persian border found themselves in the midst of civil strife. In 313, when Constantine I proclaimed Christianity a tolerated religion in the Roman Empire, the Sassanid rulers of Persia adopted a policy of persecution against Christians, including the double-tax of Shapur II in the 340s. The Sassanids feared the Christians as a subversive and possibly disloyal minority. In the early-5th century official persecution increased once more. However, from the reign of Hormizd III (457–459) serious persecutions grew less frequent and the Persian church began to achieve a recognized status. Through the Battle of Avarayr (451) and the resultant treaty of 484, for example, the Persian Empire's numerous Armenian subjects gained the official right to profess Eastern Christianity freely. Political pressure within Persia and cultural differences with western Christianity were mostly to blame for the Nestorian schism, in the course of which the Roman Empire church hierarchy labelled the Church of the East heretical. The bishop of Ctesiphon (the capital of the Sassanid Empire) acquired the title first of catholicos, and then patriarch, completely independent of any Roman/Byzantine hierarchy.