Union of Church and State in the Late Roman Empire

Below are some extracts from WK Boyd’s 1905 book, The Ecclesiastical Edicts of the Theodosian Code. This book discusses the union of church and state in the late Roman Empire and the role of the emperors in church affairs. Boyd’s book was a historical treatise and, therefore, less suspect to theological contamination. The complete book may be obtained from Archive.org or Internet Archive.

Boyd’s source

Boyd’s source was “the Theodosian code,” a compilation of the imperial decrees and edicts since Constantine; published in the year 438 (pages 10-12 from Boyd’s book). This document was requested not by the famous Theodosius I who became emperor in 379, but by Theodosius the Younger (408-450) (page 11).

Union of Church and State

One particular interest of this document was “the blending of civil and ecclesiastical authority in the later Roman Empire.” “This union of secular and religious forces” may be seen in “the ecclesiastical edicts of Constantine and his successors.” (page 9)

For ages, the Roman government was united “with the ancient pagan religious systems.” The “ecclesiastical edicts of Constantine and his successors” have “severed” that “alliance.” These edicts were “only one phase in the ever-increasing influence of the church.” “Constantine established the precedent for imperial intervention in ecclesiastical affairs” (page 33). “Gratian and Theodosius finally and decisively fixed the alliance of the state with ecclesial creed and persecution” (page 33).

The “bishops … in the days of the later Roman Empire“ were not only responsible for church matters. They also had “political and social power.” This made “their election … a matter of public importance.” The emperors, for that reason, did “exercise a direct influence on elections” of bishops through ecclesiastical synods which the emperors often convened and attended (page 64). For example:

Constantine wrote to the council and people of Antioch not to choose Eusebius of Caesarea as bishop of that city” (page 64).

Constantine’s son “Constantius convened ‘an assembly of bishops of Arian sentiment’ and deposed Paul of Constantinople” (page 64).

“Constantine gave the episcopal (papal) courts a place in the judicial system of the empire.” The authority given to the bishop “in the system of justice was similar to that of the judges of the public law courts.” In fact, the power of the bishop’s office “as arbitrator was that of an authority transcending (exceeding) the regular civil courts.” (pages 90-91)

Why emperors became involved in church matters

“Constantine desired that the church should contribute to the social and moral strength of the empire.” Therefore, “religious dissension was (regarded as) a menace to the public welfare.” Therefore, “if necessary, secular authority might be exercised for … suppression” of “religious dissension.” (page 34)

This is also why Constantine interceded “for the settlement of the Arian controversy.” His interest was not “the protection of any creed or interpretation of Christian doctrine.” Instead, his goal was “to preserve unity within the church.” He believed that “disunity in the church” was a danger to the state “more grievous than any kind of war.” (page 37)

A consequence of the Nicene Creed

“The creed of Nicaea, sanctioned by imperial decree … only added increased confusion and complication to the problem it was intended to solve” (page 38).

Theodosius I

“A far more drastic policy toward heresy was pursued by Theodosius:

He issued an edict” (page 44) in February 380 that is known as the Edict of Thessalonica. This decree made the Trinity branch of the church the only legal religion in the empire. All other branches of Christianity and all other religions were outlawed. All his subjects, including pagans, were required to believe in the Trinity. See Theodosius for a discussion.

“In January of the following year, another edict forbade the heretics to settle in the cities … and (that) the Nicene faith … to be always maintained.”

“In the same year, after the reformulation of the Nicene doctrine by the Council of Constantinople, which was convoked by the emperor to adjust problems of doctrine, the procouncil of Asia was ordered to deliver all churches to these bishops ‘who profess that the Father, Son and Holy Spirit are one majesty and virtue, the same glory, one light making no confusion by profane division‘.” (pages 45-46)

It is interesting to compare this wording with the Creed of Constantinople of the year 381. The emperor‘s edict sounds more like the Athanasian Creed than the Nicene Creed.

“The Arians did not surrender without protesting their right to exist. In the east, ‘great disturbances arose as they were ejected from the churches'” (page 46).

“The case frequently cited as typical of the conditions and opinions of the age regarding the treatment of heretics is the execution of Priscillian and … of his followers. In 384 Priscillian was condemned by the synod of Bordeaux for teachings tainted with Manichaeism. … Maximum, the usurping Augustus of the West … appointed the Prefect Ennodius to conduct the trial (in a secular court) … Priscillian was found guilty of magic … (and) put to death by the sword, and a number of his followers were executed or exiled. Not till the fifth century … was the death penalty for heresy justified by ecclesiastical theory” (pages 60-61).1Boyd cites Sulpicius Severus Chronicon, ii, 46, 5 as the source for the persecution of Priscillian.

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    Boyd cites Sulpicius Severus Chronicon, ii, 46, 5 as the source for the persecution of Priscillian.