This article gives a historical overview of Christian positions on Persecution of Christians, persecutions by Christians, religious persecution and toleration. Christian theologians like Augustine of Hippo and Thomas Aquinas legitimized religious persecution to various extents, and during the Late Antiquity and the Middle Ages, Christians considered heresy and dissent to be punishable offences. However, Early modern Europe witnessed the turning point in the history of Christian thought on persecution and tolerance. Christian writers like John Milton and John Locke argued for limited religious toleration, and later secular authors like Thomas Jefferson developed the concept of religious freedom. Christians nowadays generally accept that heresy and dissent are not punishable by a civil authority. Many Christians "look back on the centuries of persecution with a mixture of revulsion and incomprehension."
Early Christianity was a minority religion in the Roman Empire and the early Christians were persecuted during that time. After Constantine I stopped the persecution of Christians, it became the dominant religion in the Roman Empire. Already beginning under his reign, Christian heretics were persecuted; The most extreme case (as far as historians know) was the burning of Priscillian and six of his followers at the stake in 383. In the view of many historians, the Constantinian shift turned Christianity from a persecuted into a persecuting religion. Beginning in the late 4th century A.D. also the ancient pagan religions were actively suppressed.