The controversial issue of Constantine’s supposed conversion to christian mysticism has bedevilled serious students of his age, ever since the time of Gibbon (1737 – 1794). This historian, with the typical scepticism of the eighteenth century rationalist, first confronted the conventional view of Constantine, portrayed as champion of the church and first Christian emperor. This traditional, over-simplified and idealised picture of the emperor had its origins in the writings of certain early church historians, who left accounts contained references to miraculous “visions” and “celestial signs”. Obviously these types of events lie outside the legitimate realm of secular historiography. In any event it is quite impossible to ascertain with any real degree of certainty that the purported religious conviction of anyone at all is truly genuine. Essentially this is always a private matter between each individual and his own god. However we may legitimately accept that a hypothesis for any motive or conviction, attributed to a historical figure, is proven historiographically, if all the established facts of that person’s deeds and behaviour, as well as his surviving correspondence and reported utterances, are consistent with this deduction, always provided that the integrity of the sources for this information can be verified with a high degree of certainty.
The direct results of the events surrounding this particular alleged conversion (whether true or pretended) were absolutely pivotal for setting out the future course for both the Roman Empire and for the Christian Church, the joint foundation stones of Western Civilisation, as we know it today. An examination of the motives that likely influenced Constantine in his rise to power and guided his subsequent acts is therefore essential, in order to begin to understand his epoch, which brought about such fundamental changes to the philosophical concept of the state and particularly in its relationship to the religious life of its people.
A critical examination of the integrity of the major literary sources for Constantine’s reign is therefore of cardinal importance. By far the most important sources, for this period and especially for the subject of his apparent conversion, are the contemporary Christian historians, Eusebius of Caesarea (AD 260 – 340) and Lactantius (AD 250 – 320), who was a native of the province of Africa. If we can satisfy ourselves, from an analysis of these two primary sources, that their record of Constantine’s behaviour is consistent and plausible and moreover is compatible with the surviving documentary, numismatic, archaeological and other evidence, then on a strict balance of probabilities we may legitimately accept (or reject) the proposition that he was an authentic convert. However should the literary record prove to be flawed, containing sections that are substantially unfair as a result of bias, or to some degree inconsistent with established facts, due to errors, untruths, illogical statements or unsubstantiated deductions, then the faulty material must be rejected. This may leave insufficient tested material remaining to give any certainty for resolving the issue. In that event, we must remain content with the unsatisfactory conclusion that the issue is not decidable, or at best, one point of view may be accepted, with qualifications, as a working hypothesis, for seeming the more probable of the two options. The yardstick for assessing the validity of these sources will thus be the degree to which they can sustain a definitive answer to our proposition.
Eusebius, church historian and Christian theologian, was a renowned scholar and prolific writer. He was, inter alia, the author of “Ecclesiastical History (HE)” written in 315 and revised ten years later. He is also believed to be the author of “The life of Constantine (VC)”, which is a biography, containing invaluable transcripts of important official letters and documents, relating to Constantine’s reign (written c340 – if the authorship is allowed). He was also known as Eusebius Pamphili, in commemoration of his martyred friend, colleague and literary collaborator, Pamphilus of Caesaraea. After Pamphilus’ death he moved to Tyre, but fled to Egypt during the persecution initiated by the emperor Galerius in 304. Following the retraction of the persecution by the “Edict of Toleration”, promulgated by Galerius at Nicomedia on 30 April 311 (ref: Ecclesiastical History VIII. XVII. 6-10), he was able to return to Palestine, becoming bishop of Caesarea in 314. He was the confidant and adviser of Constantine from about 324 and tried to secure a moderate outcome from the Council of Nicaea, in which he gave the opening address. His writing was in Greek.