1. The Eutychian heresy is totally opposed to the Nestorian. Nestorius taught that there were two Persons and two Natures in Christ. Eutyches, on the contrary, admitted that there was but one Person, but he asserted that there was but one Nature, likewise, for the Divine Nature, he said, absorbed the human nature. Hence, Nestorius denied the Divinity of Christ, Eutyches his humanity; so both one and the other destroyed the mystery of the Incarnation and of the Redemption of man. We do not exactly know how Eutyches explained his doctrine of only one Nature in Christ. In the Council held by St. Flavian he merely explained it in these terms : ” That our Lord was of two Natures before the union, but after the union only of one Nature.” And when the Fathers pressed him to explain more clearly, he only answered, that he came not to dispute, but only to suggest to his Holiness what his opinion was (1). Now, in these few words Eutyches uttered two blasphemies : First That after the Incarnation there was only one Nature in Christ, that is, the Divine Nature, as he understood it; and, secondly That before the Incarnation of the Word there were two Natures, the Divine and the human nature. As St. Leo says, writing to St. Flavian : “Cum tam impie duarum Naturarum ante Incarnationem Unigenitus Dei Filius fuisse dicatur, quam nefarie postquam Verbum caro factum est, Natura in eo singular is asseritur.”


2. Returning, however, to the principal error, that the two Natures became one after the Incarnation, that might be asserted to have happened in four ways : First That one of the Natures was changed into the other. Second That both Natures were mixed up and confused, and so only formed one. Third That without this mixing up, the two Natures in their union formed a third. And, fourth That the human was absorbed by the Divine Nature, and this is, most probably, the opinion of the Eutychians. Now, the Catholic dogma is totally opposed to this unity of the Natures in Christ, no matter in what sense the Eutychians understood it. This is what we are going to prove.








3. This dogma is proved from the passages of Scripture already quoted against Arius and Nestorius, in which Christ is proved to be both God and man; for, as he could not be called God, if he had not perfect Divine Nature, so he could not be called man, if he had not perfect human nature. We will, however, set the matter in a clearer light. In the Gospel of St. John (Chap, i), after saying that the Word is God ” In the beginning was the Word, and the Word was with God, and the Word was God” it is stated in the 14th verse, that human nature was assumed by the Word : ” The Word was made flesh, and dwelt among us.”


(1) Tom. 4; Concil. Labboei. p.  223, 226.


Hence, St. Leo, in his celebrated Epistle to St. Flavian, says : ” Unus idemque (quod sæpe dicendum est) vere Dei Filius, et vere hominis Filius. Deus per id quod in principio erat Verbum, et Verbum erat apud Deum : Homo per id quod Verbum caro factum est, et habitavit in nobis. Deus per id quod omnia per ipsum facta sunt, et sine ipso factum est nihil : Homo per id quod factus est ex muliere, factus sub lege.”


4. The two Natures in Christ are also most clearly proved by that celebrated text of St. Paul (Philip, ii, 6), which we have so frequently quoted : ” For let this rnind be in you which was also in Christ Jesus, who being in the form of God, thought it not robbery to be equal with God, but emptied himself, taking the form of a servant, being made in the likeness of man. and in habit formed as a man.” Here the Apostle allows in Christ the form of God, according to which he is equal to God, and the form of a servant, according to which he emptied himself, and was made like unto men. Now, the form of God and the  form of a servant cannot be the same form, nor the same Nature; because, if it was the same human nature, we could not say that Christ is equal to God; and, on the contrary, if it was the same Divine Nature, Christ could not be said to have emptied himself, and made himself like unto man. We must, therefore, admit that there are two Natures in Christ, the Divine Nature, by which he is equal to God, and the human nature, by which he is made like unto man.


5. Besides, this text proves that the two natures in Christ are unmingled and unconfused, each retaining its own properties, because, if the Divine Nature was changed in him, he would no longer be God when he became man; but that would contradict what St. Paul says (Rom. ix, 5) : ” Of whom is Christ according to the flesh, who is over all things God blessed forever.” Thus Christ is, at the same time, God and man, according to the flesh. If the human was absorbed by the Divine Nature, or even changed into a Divine substance, as the Eutychians say, as we learn from Theodoret in his Dialogue Inconfusus, where Eranistes, an Eutychian, says: “Ego dico mansisse Divinitatem, ab hac vero absorptam esse humanitatem …….ut mare mellis guttam si accipiat, statim enim guttailla evanescit maris aquæ permixta ……Non dicimus delatam esse naturam, quæ assumpta est, sed mutatam esse in substantiam Divinitatis.” Thus the human nature, according to them, was absorbed in the Divine Nature, like a drop of honey in the ocean. But supposing that to be the fact, Christ could no longer be called man as he is in the Gospels, and all the New Testament, and as St. Paul calls him in the text already quoted, and again, in his I. Epistle to Timothy (ii, 6) : ” The man Christ Jesus, who gave himself in redemption for all.” Neither could we say that he emptied himself in human nature, if it was changed into the Divinity. If the human nature, therefore, was thus mixed up with the Divine Nature, Christ would no longer be either true God or true man, but some third sort of Person, which is contrary to the whole teaching of the Scriptures. We are bound, therefore, to conclude that the two Natures in Christ are unmingled and unconfused, and that each Nature retains its own properties.


6. All those other passages of the Scriptures which affirm that Christ had a true body and a true soul united to that body, confirm the truth of this dogma, for from this it is manifest that the human nature remained entire and unmixed in Christ, and was not confused with the Divine Nature, which remained entire also. That Christ had a real body is proved by St. John, against Simon Magus, Menander, Saturninus, and others, who asserted that his body was not a true, but only an apparent one. Hear the words of St. John : ” Every spirit that confesseth that Jesus Christ is come in the flesh is of God, and every spirit that dissolveth Jesus Christ (in the Greek version who does not confess that Jesus is come in the flesh) is not of God, and this is Antichrist” (I. Epis. iv, 2, 3.) St. Peter (I. Epis. ii, 24), says : ” Who of his ownself bore our sins in his body on the tree ;” and St. Paul, writing to the Collossians (i, 22), says : ” He hath reconciled in the body of his flesh through death ;” and again, writing to the Hebrews (x, 5), he puts into the mouth of Jesus these words of the thirty-ninth Psalm : ” Sacrifice and oblation thou wouldst not, but a body thou hast fitted to me.” I omit many other passages in which the body of Christ is mentioned. Our Lord himself speaks of his soul in St. John (x, 15), when he says: ” I lay down my life (animam) for my sheep ;” and again (ver. 17) : ” I lay down my life (animam), that I may take it again. No man taketh it away from me, but I lay it down of myself.” In St. Matthew he says (xxvi, 38) : ” My soul is sorrowful unto death.” It was his blessed soul that was separated from his body at his death, when St. John says (xix, 30), that, ” bowing his head, he gave up the ghost.” Christ, therefore, had a true body and a true soul united to each other, and he was, therefore, a true man, and that this body and this soul existed whole and entire after the hypostatic union, is clear from the passages quoted, all of which refer to Christ, after this union had taken place. There is no foundation, therefore, for asserting that his human nature was absorbed into the Divinity, or changed into it.


7. A confirmatory proof is given by those texts in which matters are attributed to Christ which belong to the human nature alone, and not to the Divine Nature, and others, which properly belong to the Divine Nature alone, and not to the human nature. As regards the human nature it is certain that the Divine Nature could not be conceived, could not be born, or grow up to manhood, or suffer hunger or thirst, or weakness, or sorrow, or torments, or death, for it is independent, impassible, and immortal; these feelings belong to human nature alone. Now Jesus Christ was conceived and born of the Virgin Mary (Matt. i). He grew up to manhood : “he advanced in wisdom and in age, and grace with God and man” (Luke, ii, 52); he fasted and was hungry : ” When he had fasted forty days and forty nights, afterwards he was hungry” (Matt, iv, 2); he was wearied : ” Jesus therefore being weary with his journey, sat thus on the well” (John, iv, 6); he wept : ” Seeing the city he wept over it” (Luke, xix, 41); he suffered death : ” He was made obedient unto death, even to the death of the Cross” (Phil, ii, 8); and ” saying this, he gave up the ghost” (Luke, xxiii, 45); ” And crying out with a loud voice he gave up the ghost” (Matt, xxvii, 50). It does not belong, either, to the Divine Nature to pray, to obey, to offer sacrifice, to humble himself, and such like actions, all of which the Scriptures attribute to Jesus Christ. All these actions, therefore, belong to Jesus as man, and, consequently, after the Incarnation he was true man.


8. As to the second part, it is certain that human nature cannot be consubstantial to the Father, nor have all that the Father has, nor operate all that the Father operates; it cannot be eternal, nor omnipotent, nor omniscient, nor immutable, and still all these attributes are properly applied to Jesus Christ, as we have proved against Arius and Nestorius; therefore in Jesus Christ there is not alone the human, but also the Divine Nature. St. Leo in his Epistle to St. Flavian states this so forcibly that I cannot omit quoting the original : ” Nativitas carnis manifestatio est humanæ naturæ : partus Virginis Divinæ est virtutis indicium: infantia Parvuli ostenditur humilitato eunaram : magni tude Altissimi declaratur vocibus Angelorum. Similis est redimentis homines, quem Herodes impius molitur occidere; sed Dominus est omnium, quem Magi gaudentes veniunt suppliciter adorare. Cum ad Præcursoris sui baptismum venit, ne lateret, quod carnis velamine Divinitas operiatur, vox Patris de Cœlo intonans dixit : “Hic est Filius mcus dilcctus, in quo mihi bene complacui. Sicut hominem Diabolica tentat astutia, sic Deo Angelica famulantur officia. Esurire, sitire, lassescere, atque dormire, evidentur humanum est : quinque panibus quinque millia hominum satiare, targiri Samaritanæ aquam vivam, &c., sine ambiguitate dicendum est. Non ejusdem naturæ est fiere miserationis affectu, amicum mortuum, et eundem quatriduanao aggere sepulturæ ad vocis impcrium excitare redivivum : aut in ligno pendere, et innoctem luce conversa omnia clementa tremefacere : aut clavis transfixuin esse, et Paradisi portas fidei Latroni aperire. Non ejusdem naturæ est dicere : Ego et Pater unum sumus, et dicere: Pater major me est.”


9. Besides the Scripture, tradition has constantly preserved the faith of the two Natures in Christ. In the Apostles Creed we see this marked down most clearly : ” I believe in Jesus Christ, his only Son, our Lord” here is the Divine Nature ” Who was conceived of the Holy Ghost, born of the Virgin Mary, suffered under Pontius Pilate, was crucified, dead, and buried” here is the human nature. In the Creeds of Nice and Constantinople the Divine Nature is thus explained : ” And in our Lord Jesus Christ, the Son of God true God of true God, born, not made, consubstantial to the Father, by whom all things were made.” Then the human nature is explained: ” Who for us man, and for our salvation came down from heaven, and was incarnate of the Holy Ghost by the Virgin Mary, and was made man : he suffered, was crucified, died, and arose the third day.”


10. Even before the Eutychian heresy sprung up at all, it was condemned by the First Council of Constantinople, in which the Fathers, in their Synodical Epistle to Pope St. Damasus thus write : ” Se agnoscere Verbum Dei ante secula omnino perfectum et perfectum hominem in novissimis diebus pro nostra salute factum esse.” And St. Damasus, in the Roman Synod (1), had already defined against Apollinares that in Christ there was both a body and an intelligent and rational soul, and that he had not suffered in the Divinity, only in the humanity. In the Council of Ephesus the Second Epistle of St. Cyril to Nestorius in which the dogma of two Natures distinct and unmixed in Christ is expressed, was approved. Here are the words : ” Neque enim dicimus Verbi naturam per sui mutationem carnem esse factam, sed neque in totum hominem transformatam ex anima, et corpore constitutam. Asserimus autem Verbum, unita sibi secundum hypostasim carne animata, rationali anima, inexplicabili, incomprehensibilique modo hominem factum, et hominis Filium extitisse…….. Et quamvis naturæ sint diversæ, veram tamen unionem cocuntes, unum nobis Christum, et Filium effecerunt. Non quod naturarum differentia propter unionem sublata sit, verum quorum Divinitas, et humanitas secreta quadam ineffabilique conjunctione in una persona unum nobis Jesum Christum, et Fili um constituerint.”


11. Besides the Councils we have the authority of the Holy Fathers, likewise, who wrote previous to the Eutychian heresy. These were quoted in the Actio. II. of the Council of Chalcedon, and Petavius (2) collected a great number, but I will only call the attention of the reader to a few. St. Ignatius the Martyr (3) thus expresses the doctrine of the two Natures : ” Medicus unus est et carnalis, et spiritualis, genitus et ingenitus, seu factus et non factus, in homine cxistens Deus, in morte vita vera, et ex Maria et ex Deo, primum passibilis, et tune impassibilis, Jesus Christus Dominus noster.”


(1) Vide t. 2, Concil.p.  900, 964. (2) Petav. l. 3, de Incar. c. 6, 7.  (3) St. Ignat. Ep. Eph. 7. 


St. Athanasius wrote two books against Apollinares, the predecessor of Eutyches. St. Hilary says (4) : “Nescit plane vitam suam, nescit qui Christum Jesum ut verum Deum, ita et verum hominem ignorat.” St. Gregory of Nazianzen says (5) : ” Missus est quidem, sed ut homo; duplex enim erat in eo natura.” St. Amphilochius, quoted by Theodoret in the Dialogue Inconfusus, writes thus : “Discerne naturas, unam Dei, alteram hominis; neque enim ex Deo excidens homo factus est, neque proficiscens ex homine Deus.” St. Ambrose says (6) : ” Servemus distinctioncm Divinitatis, et carnis, unus in utraque loquitur Dei Filius, qui in eodem utraque natura est.” St. John Chrysostom says (7) : ” Neque enim (Prophetæ carnen dividit a Divinitate, neque Divinitatem a carne; non substantial confundens, absit, sed unionem ostendens Quando dico cum fuisse humiliatum, non dico mutationem, sed humanæsusceptæ nature demissionem.” St. Augustine writes (8) : ” Neque enim ilia susceptione alterum eorum in alterum conversum, atque mutatum est; nec Divinitas quippe in creatnram mutata est, ut desisteret esse Divinitas; nec creatura in Divinitatem, ut desisteret esse creatura.”


12. I omit a great number of authorities of other Holy Fathers taken into account by the Council of Chalcedon, consisting of nearly six hundred Fathers, in which Eutyches was condemned, and which thus  defined the doctrine of the Church (Act. V.) : ” Sequentes igitur Ss. Patres unum eundem confiteri Filium et Dominum nostrum Jesum Christum consonanter omnes docemur, eundem perfectum in Deitate, et eundem perfectum in humanitate, Deum verum, et hominem verum; eundem ex Anima rationali, et corpore; consubstantialem Patri secundem Deitatem, consubstantialem nobiscum secundum humanitatcm; ante secula quidem de Patre genitum secundum Deitatem, in novissimis autem diebus eundem propter nos, et propter nostram salutem ex Maria Virgine Dei Genitrice secundum humanitatem, unum eundum Christum, Filium, Dominum, unigenitum in duabus naturis inconfuse, immutabiliter, indivise, inseparabiliter agnoscendum: nusquam sublata differentia naturarum propter unitionem, magisque salva proprietate utriusque naturæ, et in unam Personam, atque substantiam concurrentes.”


(4) St. Hil. l. 9, de Trin. (5) St. Greg. Nazian. Orat. de Nat. (6) St. Ambrose, l. 2, de Fide, c. 9, alias 4, n. 79.  (7) St. Chiysos. in Psalm xliv, n. 4.  (8) St. Aug. l. 1, de Trin. c. 7 n. 14.


It is related that the Fathers, after hearing the Dogmatical Epistle of St. Leo to St. Flavian, read in the Council, all cried out as with one voice : ” This is the faith of the Fathers and of the Apostles; we and all orthodox believers hold this faith; anathema to him who believes otherwise. Peter has spoken through Leo.” The following Councils confirmed the same doctrine, especially the Second Council of Constantinople, which, in the eighth Canon thus decreed : ” Si quis ex duabus naturis Deitatis, et humanitatis confitens unitatem factam esse, vel unam naturam Dei Verbi incarnatam dicens, non sic eam excipit, sicut Patres docuerunt, quod ex Divina natura et humana, unione secundum substantiam facta, unus Christus effectus est, sed ex talibus vocibus unam naturam, sive substantiam Deitatis, et carnis Christi introducere conatur : talis anathema sit.” The Third Council of Constantinople, in the definition of Faith, repeats the words of the Council of Chalcedon and of the Second Council of Nice : ” Duas naturas confitemur ejus, qui incarnatus est propter nos ex intemerata Dei geni trice semper Virgine Maria, perfectum eum Deum, et perfectum hominem cognoscentes.”


14. We may as well give two theological reasons for the dogma. The first is this : if the human nature Christ assumed was, after the Incarnation, absorbed into the Divinity, as the Eutychians believe, there would be an end to the mystery of Redemption, for in that case we should either deny the Passion and death of Jesus Christ altogether, or admit that the Divinity suffered and died, a supposition from which our very nature shrinks with horror.


15. This is the second reason : if, after the Incarnation but one Nature alone remained in Christ, this must have come to pass, either because one of the two Natures was changed into the other, or because both were so mixed up and confused that they formed but one alone, or at least because, being united together without confusion of any sort they formed a third Nature, just as the union of soul and body in man forms human nature. But so it is that not one of those things could take place in the Incarnation, consequently both Natures, the Divine and the human, remained entire in Jesus Christ, with all the properties of each.


16. It is impossible that one of the two Natures could be changed into the other, for in that case the Divine would be changed into the human nature, and that is totally repugnant not only to Faith but to reason itself, for we cannot imagine it even possible that the Divinity should be subject to the slightest change. Then if the human nature was absorbed and changed into the Divine Nature, we should admit that the Divinity was born in Christ, suffered, died, and rose again, which is equally repugnant to Faith and reason, as the Divinity is eternal, impassible, immortal, and unchangeable. Besides, if the Divinity suffered and died, then the Father and the Holy Ghost suffered and died also, for the Father, and the Son, and the Holy Ghost are together one Divinity. Again, if the Divinity was conceived and was born, then the Blessed Virgin did not conceive and bring forth Christ according to the one nature consubstantial to herself, and therefore she is not the Mother of God. Finally, if the humanity was absorbed into the Divinity in Christ, then he could not be our Redeemer, Mediator, and Pontiff of the New Testament, as faith teaches us he is, for these offices required prayers, sacrifice, and humiliations which the Divinity could not fulfil.


17. Therefore it cannot be asserted, first That human nature in Christ was changed into the Divine Nature, and much less that the Divine was changed into human nature. Second It never could happen that the two Natures were mixed up with each other and confused, and so formed one Nature alone in Christ, for in that case the Divinity would be changed, and would become something else; in Christ there would exist neither Divinity nor humanity, but a Nature neither Divine nor human, so that he would be neither true God nor true man. Third It never could have happened that the two Natures which existed without confusion, and totally distinct from each other, could, by uniting together, form a third nature, common to both, because this common nature must, in that case, have been produced by the two parts, which, uniting together, must be reciprocally perfect, for otherwise, if one part receives nothing from the other, but loses some of its own properties in the union, it will certainly not be as perfect as it was before. Now in Christ the Divine Nature has received no perfection from the human nature, and it could not lose anything itself, therefore it must have remained as it was before, and consequently could never form with the humanity a third nature, common to both. Besides, a common nature only springs out of several parts, which naturally require a reciprocal union, as is the case in the union of the soul with the body; but that is not the case in Christ, in whom it is not naturally requisite that human nature should be united with the Word, nor is it necessary that the Word should be united with human nature.