The Two Advents of Christ
“I saw,” [Daniel] said, “in a vision of the night, and, behold, one like the Son of man coming with the clouds of heaven, and He came even to the Ancient of days. And they who stood by brought Him near before Him. And there was given unto Him a kingdom, and glory, and dominion; and all people, tribes, and languages shall serve Him: and His dominion is everlasting, which shall never pass away, and His kingdom shall not be destroyed.”
How then do the Jews, who both confess and expect the Christ of God, reject Him because He was born of man? For since it is so arranged by God that the same Christ should twice come to the earth, once to announce to the nations the one God, then again to reign. Why do they who did not believe in His first advent believe in the second?
But the prophet comprises both His advents in few words. Behold, he says, one like the Son of man coming with the clouds of heaven. He did not say, like the Son of God, but the Son of man, that he might show that He had to be clothed with flesh on the earth, that having assumed the form of a man and the condition of mortality, He might teach men righteousness; and when, having completed the commands of God, He had revealed the truth to the nations, He might also suffer death, that He might overcome and lay open the other world also, and thus at length rising again, He might proceed to His Father borne aloft on a cloud.
On account of the goodness and faithfulness which He displayed towards God on earth, there was given to Him a kingdom, and glory, and dominion; and all people, tribes, and languages shall serve Him; and His dominion is everlasting, and that which shall never pass away, and His kingdom shall not be destroyed. And this is understood in two ways: that even now He has an everlasting dominion, when all nations and all languages adore His name, confess His majesty, follow His teaching, and imitate His goodness: He has power and glory, in that all tribes of the earth obey His precepts. And also, when He shall come again with majesty and glory to judge every soul, and to restore the righteous to life, then He shall truly have the government of the whole earth: then, every evil having been removed from the affairs of men, a golden age (as the poets call it), that is, a time of righteousness and peace, will arise.
— Lactantius. The Divine Institutes. Book IV. Ch. XII
On the Necessity of Incarnation
For if He should come to men as God, not to mention that mortal eyes cannot look upon and endure the glory of His majesty in His own person, assuredly God will not be able to teach virtue; for, inasmuch as He is without a body, He will not practice the things which He will teach, and through this His teaching will not be perfect. Otherwise, if it is the greatest virtue patiently to endure pain for the sake of righteousness and duty, if it is virtue not to fear death itself when threatened, and when inflicted to undergo it with fortitude; it follows that the perfect teacher ought both to teach these things by precept, and to confirm them by practice. For he who gives precepts for the life, ought to remove every method of excuse, that he may impose upon men the necessity of obedience, not by any constraint, but by a sense of shame, and yet may leave them liberty, that a reward may be appointed for those who obey, because it was in their power not to obey if they so wished; and a punishment for those who do not obey, because it was in their power to obey if they so wished. How then can excuse be removed, unless the teacher should practice what he teaches, and as it were go before and hold out his hand to one who is about to follow?
Man cannot be a perfect teacher unless he is also God, that he may by his heavenly authority impose upon men the necessity of obedience; nor God, unless he is clothed with a mortal body, that by carrying out his precepts to their completion in actions, he may bind others by the necessity of obedience. It plainly therefore appears, that he who is a guide of life and teacher of righteousness must have a body, and that his teaching cannot otherwise be full and perfect, unless it has a root and foundation, and remains firm and fixed among men; and that he himself must undergo weakness of flesh and body, and display in himself the virtue of which he is a teacher, that he may teach it at the same time both by words and deeds. Also, he must be subject to death and all sufferings, since the duties of virtue are occupied with the enduring of suffering, and the undergoing death; all which, a perfect teacher ought to endure, that he may teach the possibility of their being endured.
— Lactantius. The Divine Institutes. Book IV. Ch. XXIV
Mediator Between God and Man
[The Most High God] sent a teacher, as it were a living law, to found a new name and temple, that by His words and example He might spread throughout the earth a true and holy worship. But, however, that it might be certain that He was sent by God, it was befitting that He should not be born as man is born, composed of a mortal on both sides; … For He had a spiritual Father, God; and as God was the Father of His spirit without a mother, so a virgin was the mother of His body without a father. He was therefore both God and man, being placed in the middle between God and man. From which the Greeks call Him Mesites, that He might be able to lead man to God—that is, to immortality: for if He had been God only, He would not have been able to afford to man examples of goodness; if He had been man only, He would not have been able to compel men to righteousness, unless there had been added an authority and virtue greater than that of man.
— Lactantius. The Divine Institutes. Book IV. Ch. XXV