Of the Mode of Union of the Word Incarnate

Of the Mode of Union of the Word Incarnate — St. Thomas Aquinas asks: Whether the Union of the Incarnate Word took place in the nature?; Whether the union of the Incarnate Word took place in the Person?; Whether the union of the Word Incarnate took place in the suppositum or hypostasis?; Whether after the Incarnation the Person or Hypostasis of Christ is composite?; Whether in Christ there is any union of soul and body?; Whether the human nature was united to the Word of God accidentally?; Whether the union of the Divine nature and the human is anything created?; Whether union is the same as assumption?; Whether the union of the two natures in Christ is the greatest of all unions?; Whether the union of the Incarnation took place by grace?; Whether any merits preceded the union of the Incarnation?; Whether the grace of union was natural to the man Christ?.

Now we must consider the mode of union of the Incarnate Word; and, first, the union itself; secondly, the Person assuming; thirdly, the nature assumed.

Under the first head there are twelve points of inquiry:

Article 1: Whether the Union of the Incarnate Word took place in the nature?

It is said in the declaration of the Council of Chalcedon: "We confess that in these latter times the only-begotten Son of God appeared in two natures, without confusion, without change, without division, without separation---the distinction of natures not having been taken away by the union." Therefore the union did not take place in the nature.

To make this question clear we must consider what is "nature." Now it is to be observed that the word "nature" comes from nativity. Hence this word was used first of all to signify the begetting of living beings, which is called "birth" or "sprouting forth," the word "natura" meaning, as it were, "nascitura." Afterwards this word "nature" was taken to signify the principle of this begetting; and because in living things the principle of generation is an intrinsic principle, this word "nature" was further employed to signify any intrinsic principle of motion: thus the Philosopher says (Phys. ii) that "nature is the principle of motion in that in which it is essentially and not accidentally." Now this principle is either form or matter. Hence sometimes form is called nature, and sometimes matter. And because the end of natural generation, in that which is generated, is the essence of the species, which the definition signifies, this essence of the species is called the "nature." And thus Boethius defines nature (De Duab. Nat.): "Nature is what informs a thing with its specific difference,"---i.e. which perfects the specific definition. But we are now speaking of nature as it signifies the essence, or the "what-it-is," or the quiddity of the species.

Now, if we take nature in this way, it is impossible that the union of the Incarnate Word took place in the nature. For one thing is made of two or more in three ways. First, from two complete things which remain in their perfection. This can only happen to those whose form is composition, order, or figure, as a heap is made up of many stones brought together without any order, but solely with juxtaposition; and a house is made of stones and beams arranged in order, and fashioned to a figure. And in this way some said the union was by manner of confusion (which is without order) or by manner of commensuration (which is with order). But this cannot be. First, because neither composition nor order nor figure is a substantial form, but accidental; and hence it would follow that the union of the Incarnation was not essential, but accidental, which will be disproved later on (). Secondly, because thereby we should not have an absolute unity, but relative only, for there remain several things actually. Thirdly, because the form of such is not a nature, but an art, as the form of a house; and thus one nature would not be constituted in Christ, as they wish.

Secondly, one thing is made up of several things, perfect but changed, as a mixture is made up of its elements; and in this way some have said that the union of the Incarnation was brought about by manner of combination. But this cannot be. First, because the Divine Nature is altogether immutable, as has been said (), hence neither can it be changed into something else, since it is incorruptible; nor can anything else be changed into it, for it cannot be generated. Secondly, because what is mixed is of the same species with none of the elements; for flesh differs in species from any of its elements. And thus Christ would be of the same nature neither with His Father nor with His Mother. Thirdly, because there can be no mingling of things widely apart; for the species of one of them is absorbed, e.g. if we were to put a drop of water in a flagon of wine. And hence, since the Divine Nature infinitely exceeds the human nature, there could be no mixture, but the Divine Nature alone would remain.

Thirdly, a thing is made up of things not mixed nor changed, but imperfect; as man is made up of soul and body, and likewise of divers members. But this cannot be said of the mystery of the Incarnation. First, because each nature, i.e. the Divine and the human, has its specific perfection. Secondly, because the Divine and human natures cannot constitute anything after the manner of quantitative parts, as the members make up the body; for the Divine Nature is incorporeal; nor after the manner of form and matter, for the Divine Nature cannot be the form of anything, especially of anything corporeal, since it would follow that the species resulting therefrom would be communicable to several, and thus there would be several Christs. Thirdly, because Christ would exist neither in human nature nor in the Divine Nature: since any difference varies the species, as unity varies number, as is said (Metaph. viii, text. 10).

Article 2: Whether the union of the Incarnate Word took place in the Person?

We read in the Synod of Chalcedon (Part ii, act. 5): "We confess that our Lord Jesus Christ is not parted or divided into two persons, but is one and the same only-Begotten Son and Word of God." Therefore the union took place in the person.

Person has a different meaning from "nature." For nature, as has been said (), designates the specific essence which is signified by the definition. And if nothing was found to be added to what belongs to the notion of the species, there would be no need to distinguish the nature from the suppositum of the nature (which is the individual subsisting in this nature), because every individual subsisting in a nature would be altogether one with its nature. Now in certain subsisting things we happen to find what does not belong to the notion of the species, viz. accidents and individuating principles, which appears chiefly in such as are composed of matter and form. Hence in such as these the nature and the suppositum really differ; not indeed as if they were wholly separate, but because the suppositum includes the nature, and in addition certain other things outside the notion of the species. Hence the suppositum is taken to be a whole which has the nature as its formal part to perfect it; and consequently in such as are composed of matter and form the nature is not predicated of the suppositum, for we do not say that this man is his manhood. But if there is a thing in which there is nothing outside the species or its nature (as in God), the suppositum and the nature are not really distinct in it, but only in our way of thinking, inasmuch it is called "nature" as it is an essence, and a "suppositum" as it is subsisting. And what is said of a suppositum is to be applied to a person in rational or intellectual creatures; for a person is nothing else than "an individual substance of rational nature," according to Boethius. Therefore, whatever adheres to a person is united to it in person, whether it belongs to its nature or not. Hence, if the human nature is not united to God the Word in person, it is nowise united to Him; and thus belief in the Incarnation is altogether done away with, and Christian faith wholly overturned. Therefore, inasmuch as the Word has a human nature united to Him, which does not belong to His Divine Nature, it follows that the union took place in the Person of the Word, and not in the nature.

Article 3: Whether the union of the Word Incarnate took place in the suppositum or hypostasis?

Damascene says (De Fide Orth. iii, 3,4,5): "In our Lord Jesus Christ we acknowledge two natures and one hypostasis."

Some who did not know the relation of hypostasis to person, although granting that there is but one person in Christ, held, nevertheless, that there is one hypostasis of God and another of man, and hence that the union took place in the person and not in the hypostasis. Now this, for three reasons, is clearly erroneous. First, because person only adds to hypostasis a determinate nature, viz. rational, according to what Boethius says (De Duab. Nat.), "a person is an individual substance of rational nature"; and hence it is the same to attribute to the human nature in Christ a proper hypostasis and a proper person. And the holy Fathers, seeing this, condemned both in the Fifth Council held at Constantinople, saying: "If anyone seeks to introduce into the mystery of the Incarnation two subsistences or two persons, let him be anathema. For by the incarnation of one of the Holy Trinity, God the Word, the Holy Trinity received no augment of person or subsistence." Now "subsistence" is the same as the subsisting thing, which is proper to hypostasis, as is plain from Boethius (De Duab. Nat.). Secondly, because if it is granted that person adds to hypostasis something in which the union can take place, this something is nothing else than a property pertaining to dignity; according as it is said by some that a person is a "hypostasis distinguished by a property pertaining to dignity." If, therefore, the union took place in the person and not in the hypostasis, it follows that the union only took place in regard to some dignity. And this is what Cyril, with the approval of the Council of Ephesus (part iii, can. 3), condemned in these terms: "If anyone after the uniting divides the subsistences in the one Christ, only joining them in a union of dignity or authority or power, and not rather in a concourse of natural union, let him be anathema." Thirdly, because to the hypostasis alone are attributed the operations and the natural properties, and whatever belongs to the nature in the concrete; for we say that this man reasons, and is risible, and is a rational animal. So likewise this man is said to be a suppositum, because he underlies [supponitur] whatever belongs to man and receives its predication. Therefore, if there is any hypostasis in Christ besides the hypostasis of the Word, it follows that whatever pertains to man is verified of some other than the Word, e.g. that He was born of a Virgin, suffered, was crucified, was buried. And this, too, was condemned with the approval of the Council of Ephesus (part iii, can. 4) in these words: "If anyone ascribes to two persons or subsistences such words as are in the evangelical and apostolic Scriptures, or have been said of Christ by the saints, or by Himself of Himself, and, moreover, applies some of them to the man, taken as distinct from the Word of God, and some of them (as if they could be used of God alone) only to the Word of God the Father, let him be anathema." Therefore it is plainly a heresy condemned long since by the Church to say that in Christ there are two hypostases, or two supposita, or that the union did not take place in the hypostasis or suppositum. Hence in the same Synod (can. 2) it is said: "If anyone does not confess that the Word was united to flesh in subsistence, and that Christ with His flesh is both---to wit, God and man---let him be anathema."

Article 4: Whether after the Incarnation the Person or Hypostasis of Christ is composite?

Damascene says (De Fide Orth. iii, 3,4,5), "In the Lord Jesus Christ we acknowledge two natures, but one hypostasis composed from both."

The Person or hypostasis of Christ may be viewed in two ways. First as it is in itself, and thus it is altogether simple, even as the Nature of the Word. Secondly, in the aspect of person or hypostasis to which it belongs to subsist in a nature; and thus the Person of Christ subsists in two natures. Hence though there is one subsisting being in Him, yet there are different aspects of subsistence, and hence He is said to be a composite person, insomuch as one being subsists in two.

And thereby the solution to the first is clear.

Article 5: Whether in Christ there is any union of soul and body?

The body is not said to be animated save from its union with the soul. Now the body of Christ is said to be animated, as the Church chants: "Taking an animate body, He deigned to be born of a Virgin" [*Feast of the Circumcision, Ant. ii, Lauds]. Therefore in Christ there was a union of soul and body.

Christ is called a man univocally with other men, as being of the same species, according to the Apostle (Phil. 2:7), "being made in the likeness of a man." Now it belongs essentially to the human species that the soul be united to the body, for the form does not constitute the species, except inasmuch as it becomes the act of matter, and this is the terminus of generation through which nature intends the species. Hence it must be said that in Christ the soul was united to the body; and the contrary is heretical, since it destroys the truth of Christ's humanity.

Article 6: Whether the human nature was united to the Word of God accidentally?

Whatever is predicated accidentally, predicates, not substance, but quantity, or quality, or some other mode of being. If therefore the human nature accrues accidentally, when we say Christ is man, we do not predicate substance, but quality or quantity, or some other mode of being, which is contrary to the Decretal of Pope Alexander III, who says (Conc. Later. iii): "Since Christ is perfect God and perfect man, what foolhardiness have some to dare to affirm that Christ as man is not a substance?"

In evidence of this question we must know that two heresies have arisen with regard to the mystery of the union of the two natures in Christ. The first confused the natures, as Eutyches and Dioscorus, who held that from the two natures one nature resulted, so that they confessed Christ to be "from" two natures (which were distinct before the union), but not "in" two natures (the distinction of nature coming to an end after the union). The second was the heresy of Nestorius and Theodore of Mopsuestia, who separated the persons. For they held the Person of the Son of God to be distinct from the Person of the Son of man, and said these were mutually united: first, "by indwelling," inasmuch as the Word of God dwelt in the man, as in a temple; secondly, "by unity of intention," inasmuch as the will of the man was always in agreement with the will of the Word of God; thirdly, "by operation," inasmuch as they said the man was the instrument of the Word of God; fourthly, "by greatness of honor," inasmuch as all honor shown to the Son of God was equally shown to the Son of man, on account of His union with the Son of God; fifthly, "by equivocation," i.e. communication of names, inasmuch as we say that this man is God and the Son of God. Now it is plain that these modes imply an accidental union.

But some more recent masters, thinking to avoid these heresies, through ignorance fell into them. For some conceded one person in Christ, but maintained two hypostases, or two supposita, saying that a man, composed of body and soul, was from the beginning of his conception assumed by the Word of God. And this is the first opinion set down by the Master (Sent. iii, D, 6). But others desirous of keeping the unity of person, held that the soul of Christ was not united to the body, but that these two were mutually separate, and were united to the Word accidentally, so that the number of persons might not be increased. And this is the third opinion which the Master sets down (Sent. iii, D, 6).

But both of these opinions fall into the heresy of Nestorius; the first, indeed, because to maintain two hypostases or supposita in Christ is the same as to maintain two persons, as was shown above (). And if stress is laid on the word "person," we must have in mind that even Nestorius spoke of unity of person on account of the unity of dignity and honor. Hence the fifth Council (Constantinople II, coll. viii, can. 5) directs an anathema against such a one as holds "one person in dignity, honor and adoration, as Theodore and Nestorius foolishly wrote." But the other opinion falls into the error of Nestorius by maintaining an accidental union. For there is no difference in saying that the Word of God is united to the Man Christ by indwelling, as in His temple (as Nestorius said), or by putting on man, as a garment, which is the third opinion; rather it says something worse than Nestorius---to wit, that the soul and body are not united.

Now the Catholic faith, holding the mean between the aforesaid positions, does not affirm that the union of God and man took place in the essence or nature, nor yet in something accidental, but midway, in a subsistence or hypostasis. Hence in the fifth Council (Constantinople II, coll. viii, can. 5) we read: "Since the unity may be understood in many ways, those who follow the impiety of Apollinaris and Eutyches, professing the destruction of what came together" (i.e. destroying both natures), "confess a union by mingling; but the followers of Theodore and Nestorius, maintaining division, introduce a union of purpose. But the Holy Church of God, rejecting the impiety of both these treasons, confesses a union of the Word of God with flesh, by composition, which is in subsistence." Therefore it is plain that the second of the three opinions, mentioned by the Master (Sent. iii, D, 6), which holds one hypostasis of God and man, is not to be called an opinion, but an article of Catholic faith. So likewise the first opinion which holds two hypostases, and the third which holds an accidental union, are not to be styled opinions, but heresies condemned by the Church in Councils.

Article 7: Whether the union of the Divine nature and the human is anything created?

Whatever has a beginning in time is created. Now this union was not from eternity, but began in time. Therefore the union is something created.

The union of which we are speaking is a relation which we consider between the Divine and the human nature, inasmuch as they come together in one Person of the Son of God. Now, as was said above (), every relation which we consider between God and the creature is really in the creature, by whose change the relation is brought into being; whereas it is not really in God, but only in our way of thinking, since it does not arise from any change in God. And hence we must say that the union of which we are speaking is not really in God, except only in our way of thinking; but in the human nature, which is a creature, it is really. Therefore we must say it is something created.

Article 8: Whether union is the same as assumption?

The Divine Nature is said to be united, not assumed.

As was stated above (), union implies a certain relation of the Divine Nature and the human, according as they come together in one Person. Now all relations which begin in time are brought about by some change; and change consists in action and passion. Hence the "first" and principal difference between assumption and union must be said to be that union implies the relation: whereas assumption implies the action, whereby someone is said to assume, or the passion, whereby something is said to be assumed. Now from this difference another "second" difference arises, for assumption implies "becoming," whereas union implies "having become," and therefore the thing uniting is said to be united, but the thing assuming is not said to be assumed. For the human nature is taken to be in the terminus of assumption unto the Divine hypostasis when man is spoken of; and hence we can truly say that the Son of God, Who assumes human nature unto Himself, is man. But human nature, considered in itself, i.e. in the abstract, is viewed as assumed; and we do not say the Son of God is human nature. From this same follows a "third" difference, which is that a relation, especially one of equiparance, is no more to one extreme than to the other, whereas action and passion bear themselves differently to the agent and the patient, and to different termini. And hence assumption determines the term whence and the term whither; for assumption means a taking to oneself from another. But union determines none of these things. hence it may be said indifferently that the human nature is united with the Divine, or conversely. But the Divine Nature is not said to be assumed by the human, but conversely, because the human nature is joined to the Divine personality, so that the Divine Person subsists in human nature.

Article 9: Whether the union of the two natures in Christ is the greatest of all unions?

Augustine says (De Trin. i, 10) that "man is in the Son of God, more than the Son in the Father." But the Son is in the Father by unity of essence, and man is in the Son by the union of the Incarnation. Therefore the union of the Incarnation is greater than the unity of the Divine Essence, which nevertheless is the greatest union; and thus the union of the Incarnation implies the greatest unity.

Union implies the joining of several in some one thing. Therefore the union of the Incarnation may be taken in two ways: first, in regard to the things united; secondly, in regard to that in which they are united. And in this regard this union has a pre-eminence over other unions; for the unity of the Divine Person, in which the two natures are united, is the greatest. But it has no pre-eminence in regard to the things united.

Article 10: Whether the union of the Incarnation took place by grace?

Augustine says (De Praed. Sanct. xv): "By the same grace every man is made a Christian, from the beginning of his faith, as this man from His beginning was made Christ." But this man became Christ by union with the Divine Nature. Therefore this union was by grace.

As was said above (), grace is taken in two ways:--first, as the will of God gratuitously bestowing something; secondly, as the free gift of God. Now human nature stands in need of the gratuitous will of God in order to be lifted up to God, since this is above its natural capability. Moreover, human nature is lifted up to God in two ways: first, by operation, as the saints know and love God; secondly, by personal being, and this mode belongs exclusively to Christ, in Whom human nature is assumed so as to be in the Person of the Son of God. But it is plain that for the perfection of operation the power needs to be perfected by a habit, whereas that a nature has being in its own suppositum does not take place by means of a habit.

And hence we must say that if grace be understood as the will of God gratuitously doing something or reputing anything as well-pleasing or acceptable to Him, the union of the Incarnation took place by grace, even as the union of the saints with God by knowledge and love. But if grace be taken as the free gift of God, then the fact that the human nature is united to the Divine Person may be called a grace, inasmuch as it took place without being preceded by any merits---but not as though there were an habitual grace, by means of which the union took place.

Article 11: Whether any merits preceded the union of the Incarnation?

Augustine says (De Praed. Sanct. xv): "Whoever can find merits preceding the singular generation of our Head, may also find merits preceding the repeated regeneration of us His members." But no merits preceded our regeneration, according to Titus 3:5: "Not by the works of justice which we have done, but according to His mercy He saved us, by the laver of regeneration." Therefore no merits preceded the generation of Christ.

With regard to Christ Himself, it is clear from the above () that no merits of His could have preceded the union. For we do not hold that He was first of all a mere man, and that afterwards by the merits of a good life it was granted Him to become the Son of God, as Photinus held; but we hold that from the beginning of His conception this man was truly the Son of God, seeing that He had no other hypostasis but that of the Son of God, according to Luke 1:35: "The Holy which shall be born of thee shall be called the Son of God." And hence every operation of this man followed the union. Therefore no operation of His could have been meritorious of the union.

Neither could the needs of any other man whatsoever have merited this union condignly: first, because the meritorious works of man are properly ordained to beatitude, which is the reward of virtue, and consists in the full enjoyment of God. Whereas the union of the Incarnation, inasmuch as it is in the personal being, transcends the union of the beatified mind with God, which is by the act of the soul in fruition; and therefore it cannot fall under merit. Secondly, because grace cannot fall under merit, for the principle of merit does not fall under merit; and therefore neither does grace, for it is the principle of merit. Hence, still less does the Incarnation fall under merit, since it is the principle of grace, according to Jn. 1:17: "Grace and truth came by Jesus Christ." Thirdly, because the Incarnation is for the reformation of the entire human nature, and therefore it does not fall under the merit of any individual man, since the goodness of a mere man cannot be the cause of the good of the entire nature. Yet the holy Fathers merited the Incarnation congruously by desiring and beseeching; for it was becoming that God should harken to those who obeyed Him.

And thereby the reply to the First Objection is manifest.

Article 12: Whether the grace of union was natural to the man Christ?

Augustine says (Enchiridion xl): "In the assumption of human nature, grace itself became somewhat natural to that man, so as to leave no room for sin in Him."

According to the Philosopher (Metaph. v, 5), nature designates, in one way, nativity; in another, the essence of a thing. Hence natural may be taken in two ways: first, for what is only from the essential principles of a thing, as it is natural to fire to mount; secondly, we call natural to man what he has had from his birth, according to Eph. 2:3: "We were by nature children of wrath"; and Wis. 12:10: "They were a wicked generation, and their malice natural." Therefore the grace of Christ, whether of union or habitual, cannot be called natural as if caused by the principles of the human nature of Christ, although it may be called natural, as if coming to the human nature of Christ by the causality of His Divine Nature. But these two kinds of grace are said to be natural to Christ, inasmuch as He had them from His nativity, since from the beginning of His conception the human nature was united to the Divine Person, and His soul was filled with the gift of grace.