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Was Emperor Constantine a Christian?

Bill has advanced degrees in education and political science. He has been a political science teacher for over 28 years.

One of the great historical debates of western civilization is whether or not Constantine was a Christian.

One of the great historical debates of western civilization is whether or not Constantine was a Christian.

Was Constantine a Christian?

Was Constantine the Great (272-337 AD) a Christian? This has been one of the great debates of western Christendom. Was Constantine a true believer, or was he faking it?

For those of you that are Christians, I'm not addressing whether Constantine was "saved" or "born again" or what he really believed in his "heart of hearts." Rather, I'm looking at the historical evidence and asking "Which way does the evidence point"?

First, let’s consider the argument that Constantine was not a Christian.

"No. Constantine Was Not a Christian"

The argument that Constantine was not a Christian goes something like this: Constantine was more of a pagan than a Christian. After all, he had both his wife and son killed. He wasn’t even baptized a Christian until the end of his life. Why was he not identified as a Christian through baptism during his life?

Next, much is made about Constantine’s Battle at the Milvian Bridge in 312 AD where he supposedly had a vision and that this constituted a great spiritual event in his life. Yet, on the Arch of Constantine, which depicts the victory of Constantine at the Battle of Milvian Bridge, the sun god is depicted on the monument. There is no reference to the God of Christianity.

As for those that say “Constantine made Sunday a holy day because it was the day that Jesus rose from the dead," the counterargument is that Sunday was also a revered day for the Roman Sun God (hence the name “Sun-day”). Mithraism was the worship of the sun god, a religion that paralleled Christianity, but was still pagan. Constantine was really worshiping the sun-god rather than the son of God.

As for his theology, while it appears that Constantine held to some of the tenets of Christianity, it also appears that some of his views were more heterodox than orthodox and this is seen in his banishment of the trinitarian Athanasius and removal from exile the heretic Arius.

Many historians believe that Constantine's conversion to Christianity took place during the Battle of the Milvian Bridge in 312 AD, a battle in which he defeated the Roman Emperor Maxentius.

Many historians believe that Constantine's conversion to Christianity took place during the Battle of the Milvian Bridge in 312 AD, a battle in which he defeated the Roman Emperor Maxentius.

"Yes, Constantine Was a Christian"

The Killing of Family Members

The other view is that Constantine was a Christian. As for the accusations of parricide, we may have to back off on the most severe indictment. Constantine thought that his son, Crispus, was trying to supplant him or believed that his son had committed a crime. Constantine did not physically kill his son: he was tried and executed in 326.

It would have been thought of as a necessary evil to kill your enemies before they killed you, even if they were blood relatives. I don’t think the indictment stands the same with respect to his wife, Fausta. If she did bear false witness against Crispus as some believe that she did, then she deserved to die because Constantine’s son died because of her lies.

There isn't enough evidence to be conclusive here. Most historians believe that there was some connection between the deaths of Crispus and Fausta given that they happened close together. Anyway, there just isn't enough evidence to say that Constantine acted unchristian in the deaths of these two family members.


It was a common, but aberrant belief at the time that baptism washed away sins, and that if a man needed to commit necessary evils (a ruler killing his enemies, for example) that he should wait to be baptized until the end of his life. This appears to be the case in Constantine’s life. Yet, Constantine also appears to have believed that salvation is a gift of God and that it is by grace. He said, "I have experienced this in others and in myself, for I walked not in the way of righteousness. … But the Almighty God, who sits in the court of heaven, granted what I did not deserve [1]." In these words, we see the acknowledgment of sinfulness and the grace of God. This he wrote to the assembled bishops at the Council of Arles in 314 A.D.


Constantine made Sunday an official rest day. Yes, it was also a holy day for the sun god, but the prohibitions seem to be more Christian than pagan. Markets are closed; government offices are closed. The only business that was allowed to operate was the freeing of slaves. But not all activities were banned. Farming, which would have occupied most people, was not banned on Sunday.

State Religion

Yes, Constantine is partly responsible for the establishment of state religion in the Roman empire. In spite of being labeled as the man that brought about state religion, we need to keep some things in mind. First, state religion was the norm so Constantine did not erect state religion; rather he "Christianized" it. This is not an argument that he was right; but only that this would seem to be a reasonable thing for a Christian emperor to do in pagan times. Since there was no model for the institutional distinction of church and state (that won't come until much later), Constantine's actions seem reasonable for a Christian emperor, even if we do judge them to be wrong in the end. Second, Constantine does not appear to have thought that faith could be imposed. He is supposed to have said, “The struggle for deathlessness….must be free [2]."

Other Reforms

After the Battle of the Milvian Bridge in 312 AD, Constantine implements a number of first-time reforms, many of which suggest a Christian origin.

Today, if a political leader enacted the reforms that Constantine implemented, and he claimed that he believed in Christianity, most would think that he was being motivated by his religious beliefs. Our historical experience is that rulers will tend to enact what they wish because they have the power to impose their will. Power tends to reveal the heart of the ruler, rather than conceal it. Here are some of the other reforms he implemented that seem at least compatible with Christianity if not consonant with it:

  • The Cross—Constantine ordered that his troops bear the sign of the cross in battle, something that would have been distasteful for both Christians and pagans. Keep in mind that the cross was not the revered symbol that it is today. If fact, even among Christians it was still a symbol of reproach. In modern times, you might as well venerate the symbol of a guillotine or an electric chair.
  • Extended Rights to Christians—Constantine began to bring the persecution of Christians to an end with the Edict of Milan in 323 AD. Christians had their property restored that had been confiscated during the persecution of Emperor Diocletian. In his work, Church History, Eusebius said that "The whole human race was freed from the oppression of the tyrants. We especially, who had fixed our hopes upon the Christ of God, had gladness unspeakable."
  • Magic Forbidden—Laws were passed forbidding the practice of magic and divinations
  • Crucifixion Banned—Crucifixion was banned as a method of execution in 337.
  • Gladiatorial Games Banned—Gladiatorial games were banned in 325 A.D.
  • Left Pagan Rome—Constantine moved his capital from pagan Rome to Constantinople, a city that was to be a “Christian city”
  • Great churches (as opposed to temples) were built
  • Pagan Practices Reduced—Constantine ceased certain personal pagan practices, like the homage given to Jupiter on the Capitoline Hill in Rome. The images of pagan gods were removed from the coins.
  • Placing Christians in Public Office—Constantine advanced Christians to public office, and while he continued to appoint pagans into office, he was reluctant to give power to those that were unconverted.
Constantine did issue an order to ban the gladiatorial games, but was unsuccessful in abolishing the games as they continued. However, he was more successful in 337 AD in banishing crucifixion as a form of punishment.

Constantine did issue an order to ban the gladiatorial games, but was unsuccessful in abolishing the games as they continued. However, he was more successful in 337 AD in banishing crucifixion as a form of punishment.

Why Do It?

After the Battle of Milvian Bridge, the arc of Constantine’s life seems set on moving the empire in a direction that favors Christianity. In many respects, Christianity defines his life.

But, why do it? Some have said, “Well, Constantine saw the way that the political winds were blowing and so he just joined the crowd.”

Really? He alters the course of his life to join the crowd? Who does he have to impress? The Christians? They were nobodies. His peers? He would impress the pagans by staying with the traditional practices.

Also, if Constantine simply wanted to make Christianity legal, he could have done all that without implementing the other reforms, like those pertaining to Sunday or the gladiatorial games. It seems like a lot of effort—an effort of a lifetime to fake it. And, again as an emperor, why the pretension? Why did he need to feign being a believer in the first place? What legacy would he be trying to erect by feigning Christianity?

For most Christians, Constantine was too tolerant of paganism and may have even been employing some of the Mithraic beliefs in Christianity. But Constantine had no model to follow if he wished to be a Christian emperor.

The thrust of Constantine’s life was toward Christianity. He performed several deeds that we would expect a Christian ruler to perform:

  • He publicly acknowledges his sinfulness
  • He says that he accepts the grace of God
  • His reforms are exactly the kinds of reforms that we would expect of a Christian ruler.

Constantine is called “the Great.” He did more to grant protection and favor to Christians than anyone preceding him, he changed the course of Roman history, and his deeds are much of the reason why the west is still regarded as “Christian.”


[1] Christianity Today. "Constantine: First Christian Emperor." (accessed 1/9/19).

[2] Christianity Today. "Constantine: First Christian Emperor." (accessed 1/9/19).

© 2019 William R Bowen Jr


Bogdan on November 03, 2019:

He was so intimately and personally a Christian that he retained a title Pontifex Maximus (High Priest) his whole life. As a Christian he would never have held the highest pagan rank of that time

BruceH on January 11, 2019:

The answer to your question seems to be more a matter of the definition of "Christian" than one of historical facts.

There is no doubt that Constantine was a good friend to Christianity and Christians. You seem to have overlooked what may have been his greatest contribution of all, the Council of Nicaea. The precise theology of Christianity (e.g. the trinity, the divinity of Christ) would be revisited again and again for centuries, but this first ecumenical Christian council did wonders for unifying many of the lasting themes and practices of the faith as encapsulated in the resulting creed and canons.