La evolución homogénea del dogma católico

201. IMPORTANCE OF EXAMPLES.—Let us now turn to historical and concrete examples of true dogmatic developments, after the Apostles, carried out by the speculative path of reasoning properly so called. Among many others that could be adduced, we will point out ten, choosing them from the various dogmatic treatises. At the same time, in each example we will point out the major premises of faith and the minor premises of inclusive reason that have intervened in these reasonings, and we will also cite testimonies from theologians of the first rank who have understood it in this way.

Of those ten examples, some may be disputed or fail to satisfy the reader, but we harbor the conviction that the set of these ten examples must produce in every theologian free from prejudice the conviction that the evolution of dogma by way of theological conclusion is not only possible, but is a patent historical fact admitted by all the great theologians.

202. FIRST EXAMPLE.—The first example of dogmatic development that we know of, so to speak, in a solemn and authentic form, is the famous homoousion or consubstantialem, defined by the first ecumenical council against Arius. In Sacred Scripture it was explicitly stated that Jesus Christ was the Only-Begotten of the Father, true Son of God, true God like the Father; but it was not explicitly stated that He was consubstantial. And yet, that concept of consubstantiality and that word homoousion was the very thing, as St. Athanasius observes, that needed to be defined as a matter of faith if the door was to be closed to the subtle and endless arguments of the impious Arius and his numerous followers. The teaching Church, therefore, assembled in the Council of Nicaea, and, relying as always on the data of Sacred Scripture and Tradition, explicitly defined the consubstantiality of the Word, adding to the traditional creed the famous formula of consubstantialem Patri.

With that celebrated formula, the Church solemnly initiated that series of dogmatic developments through philosophical concepts, or as Cardinal Newman would say, through notional propositions, or as our objector seems to call them, through intellectual statements (190); a series that was to grow in crescendo up to the Councils of Trent and the Vatican, and that has almost reached its culmination in the immortal encyclical Pascendi, where philosophy and theology, in all that is most technical and abstruse about them, are employed by the Church for the exposition and development of dogma. But let us not digress.

As we were saying, the Council of Nicaea defined as a matter of faith the consubstantiality of the Word with the Father. That was and is a revealed truth, for only what is revealed can be defined as a dogma of faith. But where and how was that truth revealed?¹ It was [revealed] in other truths in which it is implied, and from which it emerges by reasoning or ratiocination. Those other truths are the following two: first, "Jesus Christ is the true Son of God," or "He is true God"; second, "in God there is no division of substance, but simple unity."

Indeed, if to be a true son one must be of the substance of the father, since that is the definition of filiation or generation; and if to be a son of God there must be oneness of substance with God, since in the divine substance no division is possible, it follows that between the Father and the Son in the divinity there must be consubstantiality or oneness of substance.

This reasoning, or this combination of concepts, in which consubstantiality is deduced from the concepts of filiation and divinity, pulses and even stands out in all the Holy Fathers who, before and after the Council of Nicaea, have treated the consubstantiality of the Word. To avoid lengthening the section with endless texts from the Holy Fathers, let us limit ourselves to citing the summary that three great theologians make of them, of those who have distinguished themselves by their eminent knowledge of patristics and of the so-called history of dogmas. Two of them, Petavius and Bellarmine, are well known; the third, the celebrated Greek theologian Manuel Calecas ², may well be placed alongside Bellarmine and Petavius.

Let us begin with the immortal author of the Dogmata Theologica, who expresses himself thus: "The argumentation, which proves from this that the homoousion is one with another, since it arises from it, is common to all the Greek and Latin Fathers; who, against the Arians, from this very fact affirm the equality of the Son, and, so to speak, the identity of substance with the Father, as is clear from the second and fourth books of this work" ³.

Let us now hear Bellarmine: "When the Nicene Council defined that Christ is homoousion with the Father, it drew the conclusion from the Scriptures, in which it is directly contained that there is one God, and that the Son is God; from which it follows necessarily that the Father and the Son are of the same substance and divinity" ^{4 5}.

The eminent theologian Calecas expresses himself in the same way, for he not only affirms what Petavius and Bellarmine later affirmed, but also develops it beautifully: "It is not universally an evil to reason, but only to employ principles that are not suited to what is proposed, and to think that faith can be demonstrated by natural principles. But if anyone, for that which is in question, applies to it some of those common principles of faith which exist repeatedly concerning God, and the ratified and defined opinions of the Fathers, and once these are established and none of the things set down is overthrown, concludes something consistent with them, as happened to the ancient Fathers when they disputed about the consubstantial and many other questions of faith, it will nevertheless have to be admitted that that conclusion is the sense of Scripture, which indeed depends on those principles and agrees with those causes from which it arises; then the same theological conclusion will be called known by revelation, just as the conclusions of geometry are called those which are drawn from the principles of geometry. But unless this is so, we will do away with very many things that are certain by faith and are not expressly contained in the Scriptures."

Calecas then speaks of the reasoning from two premises of faith, or from one of faith and another of reason, which the Holy Fathers are accustomed to employ in the development of dogma, and he continues thus: "But in truth, if anyone thinks that every syllogism whose two propositions are not both expressed in the Sacred Scriptures concludes falsely, he is mistaken in his opinion, and he accuses all the Doctors of the Church slanderously, who have often used arguments of this kind to establish truth in divine matters. Let this serve as an example: 'What is begotten according to substance by someone is of the same substance as the begetter; but the Son is begotten by the Father; therefore the Son is of the same substance as the Father.' For the first [premise], which is called the major, is not taken from the Sacred Scriptures, but from natural science. And yet what is inferred from it, together with the other [premise] which is of faith and of Scripture, is held as certain in faith. And if it were not lawful to argue thus, God would in vain exhort us in the Scriptures to rise to the knowledge of God from those things which we know and which we hold as nature teaches"⁶.

Finally, let us listen to none other than the Fourth Lateran Ecumenical Council, which, in its dogmatic definition against Abbot Joachim, expresses itself thus: “We, however, with the approval of the Sacred Council, believe and confess with Peter Lombard that there is one supreme reality, incomprehensible indeed and ineffable, which truly is the Father, and the Son, and the Holy Spirit. Therefore, although the Father is one person, the Son another, and the Holy Spirit another, yet they are not another reality; but what the Father is, the Son and the Holy Spirit are the very same; so that according to the orthodox and catholic faith they are believed to be consubstantial. (Now comes the reason or the why of the consubstantiality.) For the Father, indeed, from eternity, in begetting the Son, gave him his substance, according to what he himself testifies: “The Father, what he has given me is greater “than all things”. And it cannot be said that he gave him a part of the substance and retained a part for himself, since the Father’s substance is indivisible, being entirely simple. But neither can it be said that the Father, in begetting, transferred his substance to the Son, as if he so gave it to the Son that he did not retain it for himself; otherwise he would have ceased to be substance. It is clear, therefore, that without any diminution the Son received the Father’s substance by being born, and thus the Father and the Son have the same substance... If anyone, therefore, presumes to defend or approve the opinion or doctrine of the aforesaid Joachim in this matter, let him be refuted by all as a heretic”⁷

If in all this our objector sees not only true reasoning, which is the only thing we are dealing with, but even dialectical reasoning, then we do not understand what he means by reasoning.

203. SECOND EXAMPLE.—The Council of Ephesus defined as a dogma of faith, against Nestorius, that the Most Holy Virgin was truly Mother of God. That truth was and is a revealed truth.

But where and how was it revealed? It was revealed in two other truths in which it is implied, and from which it follows by reasoning. These two truths are: first, “that the Most Holy Virgin is the Mother of Jesus Christ”; second, “that Jesus Christ is true God, there being in Him no other personality or hypostasis than the divine one.” From these two revealed truths there follows as a conclusion the truth that the Virgin is the true Mother of God, and not merely the Mother of Christ, as Nestorius maintained. Let us hear St. Thomas: “Although it is not found expressly in Scripture that the Blessed Virgin is the Mother of God, it is nevertheless found in Scripture that Jesus Christ is true God, as is clear from 1 John, last chapter, and that the Blessed Virgin is the Mother of Jesus Christ, as is clear from Matthew 1. Hence it follows of necessity from the words of Scripture that she is the Mother of God⁸

This concluding character is seen even more clearly if one bears in mind that, in addition to the two revealed truths already mentioned, a truth of reason must also be brought into play for the Virgin to be truly the Mother of God. That truth of reason is that generation or maternity is not terminated in the nature, but in the person. If the action of begetting were abstractive, as is the action of understanding, and could be terminated in the nature, disregarding or abstracting from the person, the Virgin would still not be the true Mother of God, but only the mother of the humanity of Jesus Christ. Therefore, in order to deduce or develop the dogmatic truth of the divine maternity of Mary, this third truth came into play: “Being conceived or being a son is not attributed to the nature, but to the hypostasis.” Let us listen again to St. Thomas: “To be conceived and to be born is attributed to the hypostasis according to that nature in which it is conceived and born. Since therefore at the very beginning of conception the human nature was assumed by the divine person, as was said above, it follows that God can truly be said to have been conceived and born of the virgin... Hence it follows that the blessed Virgin is truly called the Mother of God”⁹

Moreover, the same Council of Ephesus, in defining the divine motherhood of Mary, clearly indicates the reasoning that has intervened in the development of that dogmatic truth. Here are the very words of the Council: “If anyone does not confess that God is truly Emmanuel, and therefore that the Holy Virgin is the Mother of God; for she gave birth according to the flesh to the Word of God made flesh; let him be anathema”¹⁰ Those therefores and those fors are the marks of informal reasoning, but true and proper reasoning, just as the buts and the therefores are of formal or dialectical reasoning. Both are the signs of human reason used as an instrument by the Church for the explanation or development of dogma, under the infallible assistance of the Holy Spirit, who is the principal cause.

This character of reasoning or of logical derivation that exists in the dogma of the divine motherhood, as well as in very many other dogmas, we believe is well expressed by the wise modern theologian Fontaine in the following words:

One quickly realizes that some of these secondary dogmas proceed from the fundamental mysteries by a kind of deduction, at once logical and ontological... These explanations, however elementary they may be, suffice nevertheless to show that the dogma of the divine maternity emerges from the notion, thoroughly grasped and correctly analyzed, of the incarnation of the Word. We say, for this reason, that this is a secondary dogma and even derived from the first; the fact that this dogma expresses flows from the other dogma and remains dependent upon it; between the two there exists an essential and necessary relationship... To place the dogma of the divine maternity beyond indisputable evidence, the Church had to study the essence of the Word, His consubstantiality with the Father, His eternal generation, and His divine personality. Then it was necessary to specify the kind of union of this eternal Word, consubstantial with the Father, with human nature, which is what we call the hypostatic union. The Greek councils, in whose bosom this long work of elucidation was carried out, completed it by proclaiming Mary true Mother of the incarnate Word, in the year 431, at Ephesus ¹¹

**204. THIRD EXAMPLE.—**The Third Council of Constantinople, the sixth among the Ecumenical Councils, defined as a dogma of faith against the Monothelites that in Jesus Christ there were not only two natures, but also two distinct wills and two distinct operations. This was and is a revealed truth. But, where and how was this truth revealed? It was revealed in two other truths, in which it is contained and from which it follows by reasoning. These truths are: First, "that Jesus Christ is not only a true man, but also a perfect man, or in a connatural state, or like us in all things, except sin or in whatever is opposed to the end of redemption." Second, "that one cannot be a perfect man (although one can be a true or essential man), nor a man in a connatural state, nor a man like us in all things, unless one has a human will and the other natural-physical powers or properties."

This reasoning, from one premise of faith and another of reason, has been the human instrument that the Church, under the assistance of the Holy Spirit, has used to know and define the dogma of the two wills in Christ. In previous sections we have already indirectly examined this point, and we have adduced in its confirmation abundant texts from Saint Thomas (101). Let us now limit ourselves to adding some new texts.

Let us listen to St. Thomas: “It would be detrimental to the perfection of the Incarnation of the Word of God if anything of those things which are natural to man were lacking in Him... But faith confesses that He is in all things without sin like unto us in natural things”¹² “It must be said that Christ ought to be made like unto His brethren in all things (as the Apostle says in Hebrews, II, 17), in those things which were necessary for their reparation. Now such things are those in which the truth of human nature consists, namely, its essential parts, and natural properties and passions by which the work of redemption was to be accomplished”¹³

Let us listen to Báñez: “Before it was defined in the Council that there is in Christ the Lord a twofold will, it was a theological conclusion; Christ has two wills, the divine and the human. For from the principle of faith that Christ is perfect man, subsisting from a rational soul and human flesh, it was evidently gathered by good consequence: therefore Christ has a created will. By the fact that this truth was defined in the Council, the conclusion is now held as immediately de fide, and is proposed to all to be believed under threat of anathema”¹⁴

Belarmine expresses the same: “And similarly the Sixth Council, when it defined that there are in Christ two wills, the divine and the human, drew the conclusion from Scripture, in which it is held that Christ is *perfect God and perfect man”¹⁵

We could continue citing numerous classical theologians of traditional theology, but we would only be repeating texts similar to those already cited in other sections. Let us, therefore, limit ourselves to citing three illustrious modern theologians: one, a Thomist; another, from the Suárez school; and the third, independent of any school.

Let the first be Fr. Berthier, who expresses himself thus: “We call that theology mixed or intermediate which depends partly on a supernatural and partly on a natural principle; such will be that conclusion, namely, that Christ possessed two intellects, two wills, and operations connatural to them. This conclusion is derived first from the principle of supernatural theology, namely, that in Christ there were two natures, and indeed perfect ones; then from the natural principle, that is, that operations proper to a perfect nature belong to it¹⁶

Second, Cardinal Franzelin, who, in his remarkable introduction to the treatise De Deo Uno, expresses himself on this matter with considerably more depth and accuracy than in his much-cited work De Divina Traditione. He says the following: “Therefore, since it is established that each premise is a revealed truth, or when one revealed premise implicitly already contains that which is set forth in the conclusion, and the other, although not revealed, evidently manifests this comprehension of the conclusion in the revealed premise (this happens, according to the Thomists, in every true and rigorous theological conclusion); without doubt the truth which is set forth in such a conclusion is revealed... An example of a conclusion in the second form (that is, of one revealed premise and another of natural reason) can be adduced against the Monothelites. The revealed proposition, that Christ, besides the divine nature, has a perfect (Very good!) human nature through which He is a true (perfect, he means) man, already contains the other truth, that Christ, besides the divine will, also has a rational will and human volitions. When, therefore, the other proposition is assumed to complete the argument; Christ is a true (perfect would be more exact) man; but essential to man (perfect man, it is understood, as he said at the beginning) is the faculty of the rational will; therefore Christ has a human will (and the same could be said: “therefore He has risibility” or any other physical property); that assumed proposition only manifests the comprehension of this conclusion in the revealed proposition... In reality, however, in these theological syllogisms for the most part (always, if it is metaphysical), the naturally certain proposition, especially where the certainty is metaphysical, only manifests the comprehension of the consequent in the revealed premise (this is, according to St. Thomas, the true office of every minor premise of reason in theology); and therefore conclusions of this kind are contained implicitly in the objective revelation, and consequently can be explicitly proposed and defined by the Church as matters of faith to be believed”¹⁷

It is pleasing to see an author of the stature and affiliation of Franzelin acknowledge that the theological conclusion is most often (plerumque) definable as of divine faith, and that it is so especially when the minor premise of reason has metaphysical certainty.

But what is pertinent to us now is his testimony that the dogma of the two wills in Christ, defined by the Sixth Ecumenical Council, is a dogma known by reasoning, and even by reasoning in which one of the premises is not revealed, but rather of natural reason.

Let the third be the illustrious Cardinal Newman, distinguished for so many titles, the modern theologian who has had the clearest vision of the existence of dogmatic progress. In his brilliant work entitled An Essay on the Development of Christian Doctrine, a work he wrote while still a Protestant and while writing which he was converted, he perhaps gave excessive importance to feeling, to life, to experience, to practice as instruments in the development of Catholic dogma, and very little or almost nothing to reasoning, toward which he almost apparently shows the same aversion that our objector seems to show. Whoever has read nothing of Newman but that work knows Newman only halfway, and will be tempted at times to see in Newman a phraseology somewhat similar to the Modernist one. But the years of Catholic life made Newman penetrate more deeply into the great problem of dogmatic development, and, instead of giving little or no importance to reasoning in that problem, he almost sometimes gives it excessive importance or, better said, gives it the importance it deserves and that St. Thomas and the great geniuses of Scholasticism always gave it. Thus, in his celebrated lectures delivered before the Catholic University of Dublin, quite a few years after his conversion, he writes the following: “Revelation is all in all in Catholic doctrine; the Apostles are its sole source; the illative method is its sole instrument, and the authority of the Church its sole sanction.” Many years still later he wrote regarding the dogma of the two wills in Christ: “The Sixth Ecumenical Council condemned the doctrine that there is but one will in Christ, although such doctrine was condemned neither by Scripture nor by tradition, except by inference ¹⁸

But before those theologians, the Prince of them all, Saint Thomas, had said it in the following words: “Nothing of natural things was lacking to Christ, who assumed the whole (entire) nature, as was said above. And therefore in the sixth council the position of those denying that there are in Christ two knowledges or two wisdoms was condemned”¹⁹²⁰

In short, even if theologians did not say so, it would suffice to look at the very words of the Council to see that reasoning was the instrument the Church used to know and define this dogma, deducing it from the revealed dogma that Christ is perfect man, or man like us in all things.

The Council says this: “This present holy and universal Synod, faithfully receiving and with open arms embracing the suggestion made by the most holy and blessed Agatho, Pope of ancient Rome... Moreover, following the synodal letters written by blessed Cyril against the impious Nestorius and to the Eastern Bishops; and also following the five holy universal Councils and the holy and approved Fathers, we define, confessing in harmony, that our Lord Jesus Christ, our true God, is one of the holy and consubstantial and life-giving Trinity, perfect in divinity and perfect in humanity, truly God and truly man, the same consisting of a rational soul and a body; consubstantial with the Father according to divinity, and consubstantial with us according to humanity, in all things like us, without sin”²¹ “And we proclaim in Him two natural wills and two natural operations, undividedly, inconvertibly, inseparably, inconfusedly, according to the teaching of the holy Fathers”²²

This reasoning or inference made by the Council, deducing the two wills and the two operations from the revealed principle of homo perfectus, is seen even more clearly in the dogmatic letter that Pope St. Agatho addressed to the Council, and which, as the Council itself confesses, was the basis of the dogmatic definition. The holy Pontiff speaks thus: “Unde consequenter, sicut duas naturas sive substantias, id est, deitatem et humanitatem, inconfuse, indivise, incommutabiliter eum habere veraciter confitemur, ita quoque duas naturales voluntates et duas naturales operationes habere, utpote perfectum Deum et perfectum hominem²³ It could not have been said more clearly²⁴

It is, therefore, beyond all doubt that reasoning, and even reasoning from one premise of faith and another of reason, has been the human instrument which the Church has used, under the assistance of the Holy Spirit, to know and define the dogma of the two wills in Jesus Christ.

AN OBJECTION.—Someone may object to me with the Gospel text: Non mea voluntas sed tua fiat, et non sicut ego volo, sed sicut tu²⁵, and that, consequently, no properly theological conclusion was necessary to define the dogma of the two wills in Christ. Here we must note three things:

First, the interpretation of these texts varies among the Holy Fathers. The term “will” can be taken in three different senses: a) free or rational will (voluntas rationis); b) necessary or natural will (voluntas naturae); c) will of sensuality or sensitive appetite (voluntas sensualitatis). If it is true that many Fathers have understood these texts in the first sense, it is no less true that others have interpreted them in the second and third senses. St. Thomas himself uses all three interpretations²⁶. The interpretation ordinarily given to these texts seems very clear to us, because we know beforehand that Our Lord was a perfect man. Without this, this interpretation would have no rigorously demonstrative value.

Second, as to what the sense of these texts may be (even if all three are admitted at once), it is beyond doubt that the councils, the popes, and a multitude of first-rate theologians expressly say—as we have seen—that the dogma of the two wills of Christ has been defined by the Church because it was deduced from another fundamental dogma: that of the "two perfect natures." But it is evident to every true Thomist that this dogma has been deduced by a conclusion properly so called²⁷

Third—and principal—that the Church has not only defined that in Christ there are two wills, but also that in Him there are two operations, two understandings, and even two kinds of knowledge. Now, this cannot be seen formally in the text Not my will but yours be done nor in any other evangelical text except by way of strict conclusion from the dogma perfect man, as Saint Thomas does: "Nothing of natural things was lacking to Christ, who assumed the whole (entire or perfect) nature, as was said above. And therefore in the Sixth Synod was condemned the position of those denying that in Christ there are two kinds of knowledge or two wisdoms"²⁸ . "Therefore, because from the fact that someone posits one action in Christ it follows that there is in Him only one nature and only one will: for this reason this position was condemned as heretical in the Sixth Synod"²⁹ .

It is, therefore, beyond doubt that reasoning, even that composed of one premise of faith and another of reason, has always been the human instrument that the Church, under the direction of the Holy Spirit, has used to know and define the dogma of the two wills, the two intellects, the two sciences, and the two operations in Jesus Christ.

205. FOURTH EXAMPLE.—The Fourth Council of Lateran, the twelfth among the ecumenical councils, defined as a dogma of faith the following proposition: "There is a certain supreme reality, the Father, and the Son, and the Holy Spirit, and it is not generating, nor generated, nor proceeding."

This proposition had been denied by Abbot Joachim against the Master of the Sentences, and the Council was not content with giving the latter his due, but rather defined his doctrine as a dogma of faith and condemned as heretics all who might presume to defend or approve the contrary. "We therefore condemn and reprobate the book or treatise which Abbot Joachim published against Master Peter Lombard, on the unity or essence of the Trinity, calling him a heretic and a madman because he said in his Sentences: 'that there is a certain supreme reality which is the Father, the Son, and the Holy Spirit, and that it is not generating, nor generated, nor proceeding...' We, however, with the approval of the sacred Council, believe and confess with Peter Lombard that there is one certain supreme reality, incomprehensible indeed and ineffable, which is truly the Father, the Son, and the Holy Spirit... and that reality is not generating, nor generated, nor proceeding... If anyone, therefore, shall presume to defend or approve the opinion or doctrine of the aforesaid Joachim in this regard, let him be confuted by all as a heretic"³⁰.

This, then, is a revealed truth. But where and how is this truth revealed? It is revealed in other truths, in which it is contained virtually and from which it proceeds, and can only proceed, by reasoning. Those other truths are: first, in the Trinity there is a real distinction of persons, but not of essence; second, if the essence were to beget or be begotten, to spirate or be spirated, there would be a real distinction in the essence, since neither generation nor spiration is possible without a real distinction of terms. From these two truths, one of faith and the other of reason, but of inclusive reason, there proceeds by rigorous reasoning the dogmatic truth defined by the Fourth Lateran Council, at least as that definition was understood by Saint Thomas Aquinas and by the generality of theologians.

This reasoning, simple in form, but full of metaphysical depth in substance, is set forth by Saint Thomas as follows: "I answer that, in this matter, Abbot Joachim erred, asserting that just as we say that God begot God, so it can be said that the essence begot the essence, considering that, on account of divine simplicity, God is not something other than the divine essence. But in this he was deceived, because for the truth of expressions, we must consider not only the things signified, but also the mode of signifying, as has been said. Although in reality God and the Godhead are the same, yet the mode of signifying is not the same in both cases. For this name, God, because it signifies the divine essence as existing in the one who has it, from its very mode of signification naturally has the property that it can stand for the person; and thus those things which are proper to the persons can be predicated of this name God, so that we may say that God is begotten or begetting, as has been said. But this name essence does not, from its mode of signification, have the property of standing for the person, because it signifies the essence as an abstract form; and therefore those things which are proper to the persons, by which they are distinguished from one another, cannot be attributed to the essence; for it would then be signified that there is a distinction in the divine essence, just as there is a distinction in the persons"³¹.

If all this is not reasoning, and even dialectical reasoning, then we do not know what some people understand by reasoning. Nor do we know what feeling can contribute to this class of purely speculative dogmas, where only the most profound metaphysical-dialectical speculations come into play as a means of explaining or developing the revealed doctrine on the unity of essence and distinction of persons in the august and fundamental dogma of the adorable Trinity.

The same line of reasoning, and how it was employed by the Council, is expressed by Melchor Cano in the following words: "Item, the Lateran Council under Innocent III, by theological reasoning against Joachim, established that the divine essence is neither begotten nor begetting. For a begotten thing and a begetting thing must be really distinct: therefore if the divine essence begot the essence, it would be distinct from itself, not by thought alone, but in reality"³².

206. FIFTH EXAMPLE.—The Second Council of Lyon, the fourteenth among the ecumenical councils, defined as a dogma of faith that the Holy Spirit proceeds from the Father and the Son not as from two principles, but as from one single principle: "Fideli ac devota professione fatemur quod Spiritus Sanctus aeternaliter ex Patre et Filio, non tamquam ex duobus principiis, sed tamquam ex uno principio, non duabus spirationibus, sed unica spiratione procedit"³³. This definition of faith was repeated by the Council of Florence: "Definimus quod Spiritus Sanctus ex Patre el Filio aeternaliter... tamquam ab uno principio et unica spiratione procedit"³⁴.

This is, therefore, a truth of faith, a revealed truth. But how and where is this truth revealed? It is revealed in other truths, in which it is contained virtually and from which it emerges by reasoning, and solely by proper and rigorous reasoning. Those other truths are: First, "In divinis omnia sunt unum et idem ubi non obstat relationis oppositio" . Second, between the spiration of the Father and that of the Son there is no relative opposition whatsoever. From these two truths, one of faith and one of reason, the defined dogma emerges by rigorous reasoning.

This reasoning, simple and brief in appearance, but also full of metaphysical depth, is set forth by Saint Thomas as follows: “I answer that it must be said that the Father and the Son are the same in all things in which the opposition of relation does not distinguish them: hence, since in the fact that they are the principle of the Holy Spirit they are not opposed relatively, it follows that the Father and the Son are one principle of the Holy Spirit”³⁵

Let us also hear Melchior Cano: “The Council of Lyon under Gregory X demonstrated by constant theological reasoning that the Holy Spirit proceeds from the Father and the Son, not as from two principles, but as from one, not by two spiriations but by one. The Father indeed and the Son, according to the faith, are one God, one power, one wisdom, briefly one in all things in which the opposition of relation does not stand in the way; for otherwise the unity of the divine nature cannot be preserved in two persons. Therefore, since in spiring there is no distinction of the Son from the Father, it follows that the Father and the Son are not two principles of the Holy Spirit, but one. From this it is understood that both erred greatly: namely, Erasmus and Ambrosius Catharinus—the former, because he believed that this conclusion pertained nothing to the faith; the latter, because he numbered it, since it is a conclusion proper to theology, among the first principles, that is, the articles of faith (articles of faith or non-derived dogmas)”³⁶

The great commentator on St. Thomas, Domingo Báñez, is no less explicit nor less interesting: “The holy Church has many times defined propositions as being of faith which were not expressly contained in the Sacred Scriptures, but which were constantly affirmed by all theologians and doctors of the Church in common, and were theological propositions, such as that Christ has a human will, which the theologians gathered from the fact that Christ, according to the faith, is true man (homo perfectus, as Báñez repeats at every step), and every man has a will; and that the Holy Spirit proceeds from the Father and the Son as from one principle: which is proved from this, that in divine matters all things are one where the opposition of relation does not intervene. Therefore, since the Father and the Son in spirating the third person have no relative opposition between themselves, it follows that they are not two principles but one. Therefore, similarly, those truths in which the whole school of theologians agrees could now be defined as being of faith; therefore, to contradict them (even before the definition of the Church) is erroneous. For example, all theologians firmly teach that Christ the Lord saw the divine essence from the instant of his incarnation: this is not found in the divine Scriptures, nor has it been defined by the Church of God as being held as of faith: but the theologians gather it through a good consequence from other places in Scripture and from the foundations of the faith, and so it is commonly received that no one can deny it without the mark of error, and it could be defined by the Church as being of faith”³⁷

This text by Báñez, like so many others that we have cited and that are found in abundance in his invaluable commentaries on the Summa Theologica, is worthy of being meditated upon by all who seek to study the Thomistic doctrine on dogmatic progress by way of conclusion or reasoning.