Constantine and Declaration of Christianity as a Legal Religion

FROM THE LECTURE SERIES: The Triumph of Christianity

By Bart D. Ehrman, The University of North Carolina, Chapel Hill

After the Battle of the Milvian Bridge, there were two co-rulers of the Roman Empire: the Christian Constantine in the west and the pagan Licinius in the east. Soon after his conversion in 312 CE, to secure their ties, Constantine arranged to have his own sister marry his co-emperor. Thus, the two rulers came together to heal the divisive religious divide by bringing to an end the great persecution against the Christians that had started 10 years earlier under Domitian.

An image of an old document written in Latin .
Constantine’s Edict of Milan was actually a letter sent to the provincial governors of the east where Christian persecution continued to drag on. (Image: Paolobon140/Public domain)

Christianity: A Legal Religion

Constantine and Licinius’s arranged to discuss this matter, resulting in an official document known traditionally as, Constantine’s Edict of Milan. However, it was not, in fact, an edict, but a letter sent to the provincial governors of the east where the persecution continued to drag on. It did not get issued from Milan but from Bithynia, after the meeting in Milan had been concluded. And it was not published by Constantine, but by Licinius, even though it appeared jointly under their two names.

The point of the letter was both to declare Christianity as a legal religion that was now to be completely tolerated and affirm the legitimacy of all forms of worship. Even though the two emperors were on opposite sides of the pagan/Christian divide, they both believed, or at least they said they believed, that divine help was necessary for the prosperity of the empire and so appeal to any and all gods was acceptable.

This was not then simply a declaration that Christianity was licit religion, let alone that Christianity would now be the official religion. Constantine never did make Christianity the religion of Rome.

Constantine’s Edict of Milan

The so-called Edict of Milan, was about religious freedom for all. Thus, the letter explicitly states the following quote:

We have given the said Christians free and absolute permission to practice their own form of worship. When you observe that this permission has been granted by us absolutely, you will understand that permission has been given to any others who may wish to follow their own observance or form of worship—a privilege obviously continent with the tranquility of our times—so that everyone may have permission to choose and practice whatever religion he wishes. This we have done to make it plain that we are not belittling any right or form of worship.

This is a remarkable statement unlike any seen before.

In the words of Constantine scholar Harold Drake, it was the first official government document in the Western world to recognize the principle of freedom of belief. With the Edict of Milan, Christianity was now, for the first time, officially recognized as completely legitimate. But so, too, were all the traditional religions of Rome. There was to be equality and toleration all around, a policy of complete noncoercion.

This article comes directly from content in the video series The Triumph of Christianity. Watch it now, on Wondrium.

Constantine Involvement in the Church

Even though Constantine did not outlaw these other religions, he did not do a whole lot to help them. On the contrary, he turned his attention to the Christian Church endowing church leaders with power, offering them special privileges, providing them with significant funding, building amazing churches.

An image of the Papal Archbasilica of St. John Lateran.
Constantine endowed church leaders with power, providing them with significant funding and building amazing churches. (Image: Borisb17/Shutterstock)

He did not just stop there; he became personally involved in the practical and theological disputes of the Christian Church, which were splitting the church. If at the time of his conversion or even at conference at Milan, Constantine was not aware of the intricacies and realities of internal Christian conflicts, he was soon to become enlightened to them, much to his chagrin.

The Donatist Controversy

The Donatist controversy was a serious dispute that was threatening to split the entire church. The background involves the first decree of Diocletian’s great persecution a decade earlier in 303 CE. A part of the decree ordered the Christian scriptures to be confiscated. The logic appears to have been that if the Christian religion was based in part on sacred books, their destruction would seriously affect the religion.

Very few people individually could afford to own Christian books. Scriptures were almost always the property of the churches. And so soldiers responsible for making the confiscations had to demand the scriptures from the church leaders who had them in their possession, either individually or in the church buildings themselves.


Many Christians thought it was a sacrilege to turn over the sacred scriptures. Those who did so were called traditores, related to the term traitor, with an equally negative literal meaning—’those who handed over’. Traditores among the clergy were not only verbally abused by other Christians but were also typically dismissed from office. But if they were unfit to serve the church, not actually legitimate ministers of God, what does that say about the validity of the Christian duties they had performed earlier as ordained members of the clergy: baptisms, giving of the Eucharist, ordaining other clergy members?

However, the traditores had obviously invalidated their sanctified status. So, were the rights they had performed earlier in their careers legitimate? That is if someone was baptized by a traditor, was the baptism valid or did it have to be performed again?

Administered by One Sanctified by God

This ended up being a huge problem. The issue was particularly acute in the very large Church of Carthage, in North Africa. Some members of the church argued that the sacraments by their very nature are sanctified by God alone, so that they are valid no matter who administers them.

However, there were hardliners who believed that true Christians would never willingly compromise their faith in the face of persecution, and they claimed that for a sacrament to be valid, it had to be properly administered by one genuinely sanctified by God, not a traitor to the cause. The most vocal supporter of this hardline view was a man named, Donatus, and so it is called the Donatist Controversy.

Q: Was the name, Constantine’s Edict of Milan, misleading?

The name, Constantine’s Edict of Milan, was misleading, as it was not an edict. It was a letter sent to the provincial governors of the east where the Christian persecution continued to drag on.

Q: What did the first decree of Diocletian’s great persecution, order?

The first decree of Diocletian’s great persecution, in 303 CE, ordered all the Christian scriptures to be confiscated.

Q: Who were the traditores?

Those who turned over the sacred scriptures were called traditores, related to the term traitor, with an equally negative literal meaning—’those who handed over’.

Keep Reading
The Rise of Constantine, the First Christian Emperor
Was Christianity Similar to Other Pagan Religions?
Diocletian and the Great Persecution of the Church