Seventeen hundred years ago this year, Constantine defeated his co-emperor Licinius, ending a series of civil wars and consolidating power as the sole emperor of Rome. At the time, Christians saw this as the defeat of old pagan ways and the triumph of a new Christian vision of Rome.  

Constantine’s turn to Christianity began before he abandoned Roman paganism. His children had been tutored by Lactantius, a Christian who opposed coerced worship and argued for religious liberty as long as a religious practice did not disrupt public order. Years later, in 312, as Constantine went into battle against a rival, he claimed to have a vision of a symbol of Christ with the words, “In this sign, conquer.” He had his soldiers paint the symbol on their shields. Constantine won the battle and converted to Christianity. The following year, he issued the Edict of Milan, which declared religious liberty across the Empire in terms that Constantine had learned from Lactantius.  

Constantine has been a controversial figure throughout Church history. Both the genuineness of his conversion and his impact on the Church have been consistently questioned and scrutinized. Many think that Constantine’s actions to tie the Church to the empire compromised the Gospel. Often, these arguments are based on a misunderstanding of what Constantine did and fail to consider what followed from the legalization of Christianity.  

The Edict of Milan legalized Christianity, along with other religions. It did not declare Christianity the official imperial religion. Though Constantine’s promotion of Christianity made it more popular, it was not named the imperial religion until Emperor Theodosius I in 380. Even then, Theodosius did not suppress paganism.  

Despite what you may have read online or seen in The Da Vinci Code movie, Constantine did not dictate doctrine to the Church. When he called the Council of Nicaea in 325 to deal with the question of the nature of Christ, a controversy that was threatening to tear the Church apart, he was performing a traditional function of Roman emperors who often acted as mediators in religious conflicts.  

Despite claims to the contrary, neither Constantine nor the Council of Nicaea had anything to do with the formation of the canon of Scripture. Constantine did not control the discussion at Nicaea, nor did he dictate the outcome. And even if he had tried, many bishops who attended the council had been tortured by his predecessor, Diocletian. If they didn’t compromise their faith, then it is silly to assume they would roll over for Constantine.   

The most direct result of Constantine’s conversion was the end of the persecution, torture, and execution of Christians. Obviously, this was welcomed by Christians in his day, but it should also be recognized as a historical good.   

The Edict of Milan also furthered Christian evangelism. Prior to Constantine, the Gospel had spread to India, Armenia, and Persia, and then from Persia across Central Asia into China by the early 600s. The legalization of Christianity led to churches being founded across the Roman Empire and missionaries sent to regions outside the empire. St. Patrick was a Romanized Briton who grew up as a Christian and brought the Gospel to Ireland. In the fifth century, a Syrian Christian named Frumentius converted the king of Axum in modern Ethiopia. Together, they evangelized that kingdom. Cyril and Methodius brought the Gospel to the Slavic people of Central and Eastern Europe in the ninth century. The evangelization of these regions can be traced to the actions of Constantine.   

Of course, the legalization of Christianity set up a tug-of-war between Church and state. Because the faith had existed as an illegal and sporadically persecuted minority religion for centuries, the Church functioned fully independent of the state. With Constantine came new questions, such as what properly belongs to Caesar and what belongs to God?  

That question remains a central issue of Western political thought today.  Even in view of the historical difficulties that emerged from his conversion, we can thank God for Constantine and for the freedom of faith and the Gospel he established. 

This Breakpoint was co-authored by Dr. Glenn Sunshine. For more resources to live like a Christian in this cultural moment, go to 

Photo Courtesy: Getty Images/andrewsafonov
Publish Date: January 9, 2024

John Stonestreet is President of the Colson Center for Christian Worldview, and radio host of BreakPoint, a daily national radio program providing thought-provoking commentaries on current events and life issues from a biblical worldview. John holds degrees from Trinity Evangelical Divinity School (IL) and Bryan College (TN), and is the co-author of Making Sense of Your World: A Biblical Worldview.

The views expressed in this commentary do not necessarily reflect those of CrosswalkHeadlines.

BreakPoint is a program of the Colson Center for Christian Worldview. BreakPoint commentaries offer incisive content people can't find anywhere else; content that cuts through the fog of relativism and the news cycle with truth and compassion. Founded by Chuck Colson (1931 – 2012) in 1991 as a daily radio broadcast, BreakPoint provides a Christian perspective on today's news and trends. Today, you can get it in written and a variety of audio formats: on the web, the radio, or your favorite podcast app on the go.