These two statements give a notion as to the extent to which the teaching of our Lord had been accepted when the event of His public execution took place, which was intended by those who brought it about to effect the destruction of His claim to teach the world, and which was calculated, according to all human judgment, to produce the effect intended. The empire of Augustus, and "the philosophy nurtured and begun together with it," took their several courses, and at the end of three hundred years the greatest man who had sat upon the throne of Augustus in all that interval came to the conclusion that the Christian Church was become the power of the time. What makes the greatness of Constantine, we have been told, makes him one of those characters in the world's history who are the individual expression of the spirit of their time, is, that he understood his time, that he perceived the weakness and powerlessness of the heathen world, the inward dissolution of the old beliefs; that the Christian faith was alone the substantial power of the time, the Christian faith, as the Corpus Christianorum, in the strong, flexible, and yet compact organisation of the Catholic Church, as seen in its one episcopate. Constantine knew Christianity only in this form; and the majestic unity into which the episcopate of the Church had already grown was for him so imposing that he saw in the Christian Church[187] the power through which the Roman empire, greatly needing a regeneration, could alone be made capable of it. That was the real power which could give a new basis to the State when it was falling into self-dissolution. To indicate the greatness of the change involved in the action of the Roman emperor, we may here use the words of St. Gregory the Great to the Anglo-Saxon King Ethelbert, when he wrote to him at the end of the sixth century: "Illustrious Son, guard carefully the grace which thou hast received by a divine gift; hasten to extend the Christian faith among the peoples subject to thee, for He will render the name of your glory yet more glorious to your posterity, whose honour you seek and preserve in the world. For so Constantine, most pious emperor of old, calling back the Roman commonwealth from the perverted worship of idols, subjected it with himself to Jesus Christ, our omnipotent Lord God."[188] But what had passed in the interval, since the officer of Tiberius crucified the Head, that the successor of Tiberius, Constantine, should recognise the Body as the only power which could hold together his tottering State? What had happened was such facts as these.