1 This only begotten Word of God reigns, from ages which had no beginning, to infinite and endless ages, the partner of his Father's kingdom. And [our emperor] ever beloved by him, who derives the source of imperial authority from above, and is strong in the power of his sacred title, has controlled the empire of the world for a long period of years.
2. Again, that Preserver of the universe orders these heavens and earth, and the celestial kingdom, consistently with his Father's will. Even so our emperor whom he loves, by bringing those whom he rules on earth to the only begotten Word and Saviour renders them fit subjects of his kingdom.
3. And as he who is the common Saviour of mankind, by his invisible and Divine power as the good shepherd, drives far away from his flock, like savage beasts, those apostate spirits which once flew through the airy tracts above this earth, and fastened on the souls of men; so this his friend, graced by his heavenly favor with victory over all his foes, subdues and chastens the open adversaries of the truth in accordance with the usages of war.
4. He who is the pre-existent Word, the Preserver of all things, imparts to his disciples the seeds of true wisdom and salvation, and at once enlightens and gives them understanding in the knowledge of his Father's kingdom. Our emperor, his friend, acting as interpreter to the Word of God, aims at recalling the whole human race to the knowledge of God; proclaiming clearly in the ears of all, and declaring with powerful voice the laws of truth and godliness to all who dwell on the earth.
5. Once more, the universal Saviour opens the heavenly gates of his Father's kingdom to those whose course is thitherward from this world. Our emperor, emulous of his Divine example, having purged his earthly dominion from every stain of impious error, invites each holy and pious worshiper within his imperial mansions, earnestly desiring to save with all its crew that mighty vessel of which he is the appointed pilot. And he alone of all who have wielded the imperial power of Rome, being honored by the Supreme Sovereign with a reign of three decennial periods, now celebrates this festival, not, as his ancestors might have done, in honor of infernal demons, or the apparitions of seducing spirits, or of the fraud and deceitful arts of impious men; but as an act of thanksgiving to him by whom he has thus been honored, and in acknowledgment of the blessings he has received at his hands. He does not, in imitation of ancient usage, defile his imperial mansions with blood and gore, nor propitiate the infernal deities with fire and smoke, and sacrificial offerings; but dedicates to the universal Sovereign a pleasant and acceptable sacrifice, even his own imperial soul, and a mind truly fitted for the service of God.
6. For this sacrifice alone is grateful to him: and this sacrifice our emperor has learned, with purified mind and thoughts, to present as an offering without the intervention of fire and blood, while his own piety, strengthened by the truthful doctrines with which his soul is stored, he sets forth in magnificent language the praises of God, and imitates his Divine philanthropy by his own imperial acts. Wholly devoted to him, he dedicates himself as a noble offering, a first-fruit of that world, the government of which is entrusted to his charge. This first and greatest sacrifice our emperor first dedicates to God; and then, as a faithful shepherd, he offers, not “famous hecatombs of firstling lambs,” but the souls of that flock which is the object of his care, those rational beings whom he leads to the knowledge and pious worship of God.
Source: Oration in Praise of Constantine (New Advent)