Such, according to Eusebius, is the first phase of the Emperor’s conversion, a conviction not of sin, but of the folly of worshipping gods who cannot or will not do anything for their votaries. But this god of his father, this single unnamed divinity, who was it? Was it one of the gods of the Roman Pantheon, Jupiter, or Apollo, or Hercules, whose special protection Constantine had claimed for himself, as Augustus had claimed that of Apollo, and Diocletian that of Jupiter? Or was it the vague spirit of deity itself, the τὸ θειον of the Greek philosophers, the divinitas of the cultured Roman, whose delicacy was offended by the grossness of the exceedingly human passions of the Roman gods and goddesses? Obviously, it must be the latter, and Eusebius tells us that Constantine offered up a prayer to this god of his father, beseeching him, “to declare himself who he was,” and to stretch forth his right hand to help. “To declare himself who he was!” (φῆναι αὐτῷ ἑαυτόν ὅστις εἴη). That had ever been the stumbling-block in the way of the acceptance by the masses of the immaterial principles propounded by the philosophers. Constantine must have a god with a name, and he must have a sign from heaven in visible proof. Many have asked for such a sign just as importunately (λιπαρῶς ἱκετεύοντι) as Constantine, but without success. To him it was vouchsafed.
CONSTANTINE’S VISION OF THE CROSS, BY RAPHAEL.
IN THE VATICAN. PHOTOGRAPH BY ALINARI.
The answer came one afternoon, when the sun had just passed its zenith and was beginning to decline. Lifting his eyes, the Emperor saw in the heavens just above the sun the figure of a cross, a cross of radiant light, and attached to it was the inscription, “Conquer by This” (τούτῳ νίκα). Eusebius admits that if any one else had told the story it would not have been easy to believe it, but it was told to him by the Emperor himself, who had confirmed his words with a royal oath. How then was it possible to doubt? Constantine was awe-struck at the vision, which Eusebius expressly declares was seen also by the entire army. All that afternoon the Emperor pondered long upon the significance of the words, and night fell while he was still asking himself what they could mean. Then, as he slept, Christ appeared to him in a dream, bearing with Him the sign that had flamed in the sky, and bade the sleeper make a copy of it and use it as a talisman whenever he gave battle. As soon as dawn broke, Constantine summoned his friends and told them of the message he had received. Workers in gold and precious stones were hastily sent for, and, sitting in the midst of them, Constantine carefully described the outline of the vision and bade them execute a replica of it in their most precious materials. This was the famous Labarum, fashioned from a long gilded spear and a transverse bar. Above was a crown of gold, with jewels encircling the monogram of Christ, and from the bar depended a rich purple cloth, heavily embroidered with gold, blazing with jewels, and bearing the busts of Constantine and his sons. It suggested the Cross just as much but no more than did the ordinary cavalry standards of the Roman armies; the sacred monogram alone indicated the supreme change which had come over the Emperor, who, in answer to his prayer, had thus found that the single Deity which his father, Constantius, had worshipped was none other than Christ, the God of the Christians. For the Emperor, desiring to know more of the Cross and the Christ, summoned certain Christian teachers in his camp to explain these things more fully to him, and they told him that “Christ was God, the only begotten Son of the one true God, and that the vision he had seen was the symbol of immortality and of the victory which Christ had won over death.” Such, according to Eusebius, was the conversion of Constantine, and such was the Emperor’s own account of the circumstances which led up to it. This was the official story, as it might have appeared in a Roman Court Circular at the time when Eusebius wrote.
But when did Eusebius write The Life of Constantine, from which we have taken this narrative? Not until Constantine himself was dead, not, that is to say, until after 337, fully a quarter of a century after the event described. The date is important. In twenty-five years a story may be transfigured out of all knowledge through constant repetition by the narrator, to say nothing of the changes it suffers if it passes in active circulation from mouth to mouth. Has this been the fate of the story of the Vision of the Cross? The Life of Constantine was not the first volume of contemporary history published by Eusebius. He had already written a History of the Church, which he issued to the world in 326. What, then, had the author to say in that year about this marvellous vision? Nothing. There is not a word about the flaming cross, or the coming of Christ to Constantine in a dream, or the fashioning of the Labarum. All Eusebius says, in his History, of the conversion of Constantine, is that the Emperor “piously called to his aid the God of Heaven and his son Jesus Christ.” It is a strange silence. If the heavenly cross had been seen by the whole army; if the current version of the story had been the same in 326 as it was in 337, it is at least difficult to understand why Eusebius omitted all mention of an event which must have been the talk of the whole Roman world and must have made the heart of every Christian exult. Such manifest signs from Heaven were scarcely so common in the opening of the fourth century that an ecclesiastical historian would think any allusion to it unnecessary. The argument from silence is never absolutely conclusive, but the reticence of Eusebius in 326 at least warrants a strong suspicion that the legend had not then crystallised itself into its final shape.
Of even greater importance are the extraordinary discrepancies between the versions of Eusebius and Lactantius. Lactantius wrote his treatise On the Deaths of the Persecutors very shortly after the battle of the Milvian Bridge, and it has a special value, therefore, as containing the earliest account of the vision. The author, who was the tutor of the Emperor’s son, Crispus, must have known all there was to be known of the incident, for he lived in the closest intimacy with the court circle. We should confidently expect, therefore, that the author who retails verbatim the conversation of Diocletian and Galerius in the penetralia of the palace of Nicomedia would be fully aware of what took place in full view of Constantine’s army.
What then is the version of Lactantius? It is that just before the battle of the Milvian Bridge, Constantine was warned in a dream to have the divine sign of the cross (cœleste signum) inscribed on the shields of his soldiers before leading them to the attack. He did as he was bidden, and the letter
, with one of the bars slightly bent—thus,
