IV. And so, beloved, it must be unreservedly acknowledged and confessed with all our hearts that this kind, in which the Word and the flesh (i.e., God and man) signify the same Son of God and Christ, has been exalted above any kind of human origin. For neither the creation of Adam from the dust of the earth, nor the creation of Eve from the flesh of a man, nor the creation into the world by the copulation of both sexes of other people can be compared with the origin of Jesus Christ. Abraham, advanced in years, gave birth to an heir by a Divine vow, and, having passed through the period of fertility, the barren Sarah conceived (Gen. 21:2). But Jacob was beloved of God before he was born (Mal. 1:2-3), and [Divine mercy], anticipating his own actions, separated him from his shaggy half-brother (Gen. 27:11). Jeremiah says: "Before I formed you in the womb, I knew you, and before you came out of the womb I sanctified you" (Jeremiah 1:5). Hannah, also being barren for a long time, gave birth to the prophet Samuel and dedicated him to God (1 Samuel 1:11-20), so that she was glorified both by birth and by vow. The priest Zacharias received holy offspring from the barren Elizabeth (Luke 1:24), and the future Forerunner of Christ, John, received a prophetic spirit from the flesh of his mother, who even before the birth of this infant revealed the Parent of the Lord with a sign of hidden [in the womb] of rejoicing (Luke 1:41). [No doubt] all this is majestic and full of miracles of divine works, but it has caused much less amazement than many others. But the Nativity of our Lord Jesus Christ surpasses all understanding and goes beyond any [earthly] experience. It cannot be compared with anything else, remaining one of a kind. To the Chosen Virgin (once from the seed of Abraham and from the root of Isaiah, foretold by the words of the prophets and secret signs) without condemnation by shame is proclaimed by the Archangel blessed fertility (Luke 1:45), which neither by conception nor by birth will violate holy virginity. And when the Holy Spirit descended upon Her and the power of the Most High overshadowed Her (Luke 1:35), the unchanging Word of God, having at His disposal an immaculate body, took on a human form, which is in no way involved in the lust of the flesh, and possesses everything that pertains to the nature of soul and body.

V. [Now] we have departed and sunk into darkness both the fables of heretical wisdom and the blasphemy of insane errors, and we (being the heavenly host that glorifies God (Luke 2:13), and the shepherds whom the angels have instructed to preach), having studied the testimonies of both natures, worship both the Word in the man Christ and the man Christ in the Word. For if, according to the words of the Apostle, he who unites with the Lord is one spirit (1 Corinthians 6:17), then the Word made flesh is all the more Christ alone. There is nothing here that does not belong to one or the other nature. Thus, according to the plan of God's mercy, we are not destroyed, but are transfigured for chastity and life. And so we recognize in our Saviour the manifested signs of both natures, that, seeing the glory of God, we do not doubt the truth of the flesh, or, seeing human humility, we do not doubt the Divine power. He abides in the form of God, Who took the form of a servant (Phil. 2:6-7). One and the same, remaining incorporeal, clothed Himself in a body. One and the same is immovable in His power and subject to suffering in our powerlessness. One and the same does not descend from the father's throne and is crucified by the wicked on the Cross. One and the same is the Conqueror of death, ascending above all the heights of heaven, and at the same time remaining with the whole Church until the end of time. Finally, when He is about to come in the same flesh in which He ascended, as He once endured the judgment of the unrighteous, so He is going to judge the actions of all mortals. Therefore, without taking time with numerous testimonies, it is enough to cite one from the Gospel of Blessed John, in which the Lord Himself says to us: Verily, verily, I say to you, the time is coming, and it has already come, when the dead will hear the voice of the Son of God, and having heard, they will live. For as the Father has life in Himself, so He gave the Son to have life in Himself. And He gave Him the power to execute judgment also, because He is the Son of Man (John 5:25-27).

Here in one sentence it is shown that One and the same is both the Son of God and the Son of Man. And from this it is clear how we should believe in the Lord Christ in the unity of the Person. He is the Son of God, thanks to whom we were born, and He, having become the Son of Man by taking on the flesh, died, according to the words of the Apostle, for our sins and rose again for our justification (Romans 4:25).

VI. Such a confession, beloved, is not afraid of any dissension and does not succumb to any error. For the mercy of God, promised from the beginning and prepared before the ages, has been revealed to us. Thanks to her alone, the bonds of captivity of the human race were able to fall, with which the seducing creator of sin bound the first man and all his descendants, and subjugated the conquered race by the original fall. The justification of people became possible only because the Only-begotten of God was vouchsafed to become the Son of Man, that is, the Only-begotten God (having the same essence) to the Father also became a true man, consubstantial in the flesh with the Mother. So let us rejoice, because we can be saved only through both essences, without separating the visible from the invisible, the carnal from the incorporeal, the passionate from the passionless, the tangible from the intangible, the image of the slave from the image of God. And though the one rests in eternity, and the other came into being in time, yet they have come together in such a unity that they can neither be separated nor destroyed, for the exalted and the exalted, the glorifyer and the glorified, are so united to one another, that in greatness and in humiliation, neither the divine in Christ is alienated from the human, nor the human from the divine.

VII. In this way, beloved, we become true Christians and true Israelites (John 1:47). Verily, then we are received into the fellowship of the sons of God. For all the saints who lived before our Saviour were justified through this faith, and through this Mystery they became the body of Christ, awaiting the universal redemption of believers in the seed of Abraham, of whom the Apostle says: To Abraham were given promises and his seed. It is not said, "And to the descendants," as of many, but as of one, "And to thy seed, which Christ eateth" (Gal. 3:16). That is why the Evangelist Matthew, in order to prove that the promise given to Abraham was fulfilled in Christ, enumerates the sequence of generations (Matthew 1:1-16) and shows which of them was blessed. The Evangelist Luke, referring to the Birth of the Lord, also enumerated in reverse order the sequence of His generations (Luke 3:23-38), testifying that those centuries that preceded the flood were also connected with this Sacrament, and every transmission of inheritance from the very beginning tended to Him in Whom alone was the salvation of all.

So we should not doubt that besides Christ there is no other name under heaven given to men by whom we must be saved (Acts 4:12), and that He, with the Father and the Holy Spirit, equal in the Trinity, lives and reigns forever and ever. Amen.

The Encyclical or Conciliar Epistle of His Holiness Leo, Archbishop of the City of Rome, Written to Flavian, Archbishop of Constantinople (Against the Heresy of Eutychius)

To his beloved brother Flavian Leo bishop.

Having read the epistle of thy love, which was so late to our astonishment, and having examined the order of episcopal acts, we have at last learned what temptation has occurred among you and has risen up against the purity of the faith, and that which formerly seemed to be a mystery has now become manifest to us. In this way, Eutyches, who was honored with the name and dignity of presbyter, turned out to be very reckless and so great an ignoramus, that the words of the prophet can be applied to him: "Do not desire to understand (to do good), the iniquity of thinking in your couch" (Psalm 35:4-5). And what is more lawless, how wicked is it to think about faith and not to follow the wisest and most experienced? But it is to this folly that those are subjected who, having encountered in some obscure difficulty in the knowledge of the truth, do not have recourse to prophetic utterances, nor to the writings of the Apostles, nor to the authority of the Gospel, but to themselves; and in this way, not wishing to be disciples of the truth, they become teachers of error. For how could he gain success in the knowledge of the sacred books of the Old and New Testaments, who did not understand the first words of the symbol itself? and what is confessed throughout the whole world by the lips of all the regenerated, this old man does not yet understand in his heart.

Therefore, not knowing what he should think about the incarnation of God the Word, and not wishing to labor in the broad field of the holy scriptures in order to be worthy of the light of knowledge, he should have received with attentive ears at least that universal and unanimous confession which all believers confess: "We believe in God the Father Almighty, and in Jesus Christ his only-begotten Son our Lord, born of the Holy Spirit and the Virgin Mary." With these three sayings the artifices of almost all heretics are overthrown. For when we believe that God is both the Almighty and the eternal Father, then this already proves that the Son is co-existent with Him, and in no way differs from the Father: for God was born of God, of the Almighty Almighty, co-eternal with the Eternal, and not later in time, not inferior in authority, not different in glory, not separate in essence. He is the eternal Father, the Only-begotten, born of the Holy Spirit and the Virgin Mary. This temporal birth did not subtract anything from that divine and eternal birth, nor added anything to it, but gave itself over entirely to the salvation of erring man, in order to conquer death, and by its power to crush the devil, who has the power of death (Heb. 2:14). For we could not have conquered the author of sin and death, if our nature had not been received and assimilated by Him, whom neither sin could wound, nor death could hold in His power. He was conceived of the Holy Spirit in the womb of the Virgin Mother, who conceived Him as a virgin, and gave birth to Him, preserving virginity.

But if he could not draw a precise understanding from this purest source of the Christian faith [2], because he had darkened for himself the splendor of the obvious truth by his own blindness, then he would turn to the teaching of the Gospel, where Matthew says: "The book of the kinship of Jesus Christ, the son of David, the son of Abraham" (Matt. 1:1); he would also seek instruction in the preaching of the Apostles, and reading in the Epistle to the Romans: Paul the servant of Jesus of Christ, called an apostle, was chosen to the gospel of God, which the prophets had previously promised in the writings of the saints, concerning his Son, who was of the seed of David according to the flesh (Romans 1:1-3); with pious curiosity he would approach the books of the prophets, and he would find the promise of God given to Abraham: "And all tongues shall be blessed in thy seed" (Gen. 22:17). And in order not to be perplexed about the quality of this seed, let him follow the Apostle, who said: "And unto Abraham were spoken the vows and his seed; And he does not say, "And seed," as of many, but as of one, "And unto thy seed, which is Christ" (Gal. 3:16). Let him also hearken with his inner ear to the prophecy of Isaiah, who said: Behold, a virgin shall conceive, and bear a son, and they shall call his name Immanuel, since it is said, God is with us (Isaiah 7:14; Matt. 1:23); I would have read these words of the same prophet with faith. A child was born unto us, O Son, and was given unto us, His ruler is upon His frame; and His name shall be called: great is the Angel of counsel, the Wonderful, the Counselor, the God of might, the Prince of Peace, the Father of the age to come" (Isaiah 9:6). Then he would not have said, idle talk, that the Word became flesh in such a way that Christ, born from a virgin's womb, had the form of a man, and did not have the true body (like the body) of the Mother. Perhaps it is not because he acknowledges our Lord Jesus Christ to be without our nature, because the angel sent to the blessed Mary said: The Holy Spirit shall come upon thee, and the power of the Most High shall overshadow thee; and that which is born (of thee) is holy, shall be called the Son of God (Luke 1:35), i.e., since the conception of the Virgin was a divine act, so was not the flesh of the begotten one of the nature of the one who was conceived? But this birth, which is exceptionally amazing and wonderfully exceptional, must not be understood in such a way that the extraordinary nature of the birth destroys the property of the species. Fruitfulness is granted to the Virgin by the Holy Spirit; and the true body is borrowed from (her) body. And when in this way Wisdom built herself a house, the Word was made flesh, and dwelt in us (John 1:14), i.e. in that flesh which She borrowed from man, and which She inspired with the spirit of rational life.

In this way; while preserving the properties of both natures and combining them into one person, humility is perceived as greatness, weakness as power, and mortality as eternity. In order to pay the debt of our nature, the passionless nature was united with the passionate nature, so that one and the same, the Mediator of God and of men, the man Christ Jesus (1 Tim. 2:5), could die according to one (nature), and could not die according to the other, as the nature of our healing required. Therefore the true God was born in the true and perfect nature of the true man: wholly in His own, wholly in ours. And we call ours that which the Creator placed in us in the beginning, and which He wanted to return to us. For in the Saviour there was not a trace of what the tempter had brought into man, and what the deceived man had allowed (into himself). And although He became a partaker of human infirmities, it does not follow from this that He became a partaker of our sins. He received the form of a servant without the defilement of sin, magnifying the human, and not diminishing the divine: for the exhaustion by which the invisible was made visible, and by which the Creator and Master of all creatures desired to be one of men, was the condescension of His mercy, and not a lack of power. Wherefore He Who, abiding in the image of God, created man, He Himself was made man, taking the form of a servant. Both natures retain their properties without any damage. As the image of God does not destroy the image of the servant, so the image of the servant does not detract from the image of God. And since the devil boasted that the man deceived by his deceit had lost the divine gifts, and, having been stripped naked of the blessing of immortality, had fallen under the severe sentence of death, and he (the devil) in his miserable condition found some consolation in the fact that he had been a participant in his treachery, that God also, by the demand of his justice, had changed his decree about the man whom he had created for such an honor: then the need arose for the dispensation of the secret council, so that the unchangeable God, whose will cannot be deprived of its inherent goodness, would fulfill, by means of the most secret sacrament, the first determination of His love for us, and that man, who had fallen into sin through the deceit of the wickedness of the devil, should not perish contrary to the divine intention.

Thus, the Son of God, having descended from the heavenly throne, comes to this valley (country) of the world, and without being separated from the glory of the Father, is born in a new way, a new birth. In a new way, because the Invisible One in His own (nature) became visible in ours, the Incomprehensible Deigned to be made comprehensible, the Eternal One began to be in time, the Lord of the universe took on the form of a servant, hiding the immensity of His majesty, the Impassible God did not disdain to become a man capable of suffering, and the Immortal One to be subjected to the law of death. And He was born of the new birth, because the immaculate virginity knew no lust, and yet provided the substance of the flesh. And so the Lord took on from His Mother nature, but not sin. And from the fact that this birth is miraculous, it does not follow that the nature of our Lord Jesus Christ, born from the womb of the Virgin, is different (from ours). For He; who is the true God, is at the same time the true man. And if the humiliation of man and the majesty of the divinity are mutually united, then in this unity there is no transformation. For as God is not changed by mercy, so man is not destroyed by glorification. Each of the two natures, in union with the other, acts as it is proper to it: the Word does what is proper to the Word, and the flesh fulfills what is proper to the flesh. One of them is a miracle, the other is subject to suffering. And just as the Word did not fall away from equality in glory with the Father, so the flesh did not lose the nature of our race. For one and the same (this must often be said) is truly the Son of God, and truly the Son of man: there is God, for in the beginning was the Word, and the Word was with God, and God was the Word (John 1:1); is man, because the Word was flesh, and dwelt in us (John 1:14); — God, because all things were by Him, and without Him there was nothing (John 1:3); — Man, because he was born of a woman, was under the law (Gal. 4:4). The birth of the flesh is the revelation of human nature; and that the Virgin gives birth is a sign of divine power. The infancy of the Child is testified to by poor swaddling clothes; and the majesty of the Most High is proclaimed by the singing of angels. He is like the newborn human (son), whom the wicked Herod would put to death; but the Lord of the universe is He to whom the Magi slavishly go to worship with joy. When He came to be baptized by His forerunner John, then, lest it should be concealed that the Divinity was hidden under the veil of the flesh, the voice of the Father thundered from heaven: "This is My beloved Son, in whom I am well pleased" (Matt. 3:17). Further, He, as a man, is tempted by the deceit of the devil; and Him, as God, is served by the ranks of angels. Hunger, thirst, labor, and sleep are obviously inherent in man; But to feed five thousand men with five loaves of bread, but to give to the Samaritan woman living water, from which the drinker shall no longer thirst, but walk with wet feet on the surface of the sea, and by the calming of the storm to tame the turmoil of the waves, without doubt, is a divine deed. Just as it is not the work of one and the same nature to weep out of compassion for a dead friend, and to raise him, after the removal of a stone from a four-day grave, to bring him to life by the power of one word; or to hang on a tree, and at the same time to turn day into night and shake all the elements: or to be nailed (to the cross), and at the same time to open the doors of paradise to the faith of the thief (we are silent about many things): so it is not only in nature to say: "I and the Father are one" (John 10:29), and "My Father is greater than Me" (John 14:29). 28). For although in the Lord Jesus there is one person, God and man, yet it is different whence comes the common humiliation of both, and another that whence proceeds their common glorification. From our nature He has mankind less than the Father, and from the Father He has a divinity equal to the Father.

On account of this unity of person, which must be understood in relation to both natures, and of the Son of man we read that He came down from heaven, while the Son of God took flesh from the Virgin from whom He was born; and vice versa, it is said of the Son of God that He was crucified and buried, whereas He suffered this not by the divinity, according to which the Only-begotten is co-existent and consubstantial with the Father, but by the feeble human nature. Hence we all confess in the Symbol (of faith) the only-begotten Son of God to be crucified and buried, in accordance with these words of the Apostle: "For if they understood, they did not crucify the Lord of glory" (1 Corinthians 2:8). And when our Lord and Saviour Himself, teaching His disciples the faith by means of questions, asked: Whom do men say that I be, the Son of man? and when they are answered, that different people think differently about this. And he said, Whom do you say I am? "I, that is, the Son of man, whom you see in the form of a servant and in a true body, whom do you consider Me to be?" Then Blessed Peter, by inspiration from above and for the benefit of his confession to all nations, answered: "Thou art the Christ, the Son of the living God" (Matt. 16:13-16). And he is worthily called blessed by the Lord, and by this prototype Stone he has acquired firmness and strength and his name — he who, according to the revelation of the Father, confessed one and the same thing, both as the Son of God and Christ; because one of these (names), taken separately from the other, did not serve for salvation, on the contrary, it was equally dangerous to confess the Lord Jesus Christ only as God, and not together as a man, or to recognize Him as a simple man, and not together with God.