Bessarion's 11 arguments on whether the Filioque could be added to the creed.

Cardinal Bessarion, during the ecumenical council of Florence’s dogmatic dialogues with the Greeks, gave 11 concise arguments which vindicate this argument. The Greeks had also conceded to this, as seen in Joseph Gill’s book on the Council of Florence.

First Argument: Any council does not only prohibit presenting another faith but also composing it. Therefore, if by saying “another faith,” it means “a faith or creed composed in different words but with the same meaning,” it would follow that all those who composed the same creed with different words but the same meaning — which almost all the holy doctors did when they professed the Catholic faith — would be under anathema. But this is not only false but also blasphemous to say. Therefore, it is not prohibited to express the same faith in different words consistent with the truth; what is prohibited is expressing a contrary and different faith.

Second Argument: Similarly, the fourth council subjects anyone who thinks or teaches differently to anathema. Therefore, if it prohibits thinking or teaching with different words, yet consistent with the truth, then all who taught the orthodox faith — in whatever words each one could — would be under anathema. For each of the saints preached the same faith with different words. Since it is inconvenient to say this, it does not prohibit different words but contrary meanings; especially since thinking refers to meanings, not to words.

Third Argument: Furthermore, the sixth council says the same things as the fourth council. Additionally, it prohibits “introducing any empty word or vain invention of any phrase to pervert what has been determined by them.” From this, it is clear that the prohibited words are those introduced to pervert the doctrines of the fathers, not those to corroborate them.

Fourth Argument: Moreover, the third council decreed that it is not right to present “another faith besides that which was declared in the Nicene Council,” and subjected those who dared to do so to anathema. But it made no mention of the creed produced by the second council — which the whole Church was to use. If they did not mention it because they considered it different and contrary to the faith of the Nicene Council, then we are mortally sinful for completely omitting the Nicene Creed, which the fathers decreed should not be abandoned, and using the creed of the second council, reading it, teaching it, and presenting it both privately and publicly. And by this reasoning, we are under anathema. If they passed over it in silence because it is identical in all respects to the Nicene Creed and contains the same faith, it is clear that it is not the same in words, for it differs significantly, having many additions and omissions. Therefore, it is the same in meaning; for this reason, the fathers of the third council considered the creeds of the first and second councils to be one. Hence, any creed composed in whatever words, containing the same meaning as the Nicene Creed, is the same as it; and nothing is against this when it says: “dare not present another creed.” “Another” is understood to mean that which contains a contrary meaning to the truth; for the creed of the second council differs from that of the first only in words, as has been said, but is judged the same by the fathers.

Fifth Argument: Likewise, each council, after reading its entire decree — not just the creed — says: “After these readings, the holy synod determines that it is not permissible to present another faith.” It is clear that when it says “after these readings,” it means the entire decree. Therefore, what follows, “it is not permissible to present another faith,” also refers to the entire decree, meaning it is not permissible to present another faith besides that which is contained in the entire decree, not just in the creed. But, in words, the fourth council composed something different from the third, the fifth from the fourth, and so on. Therefore, the rule here pertains to the whole faith and meanings, not words.

Sixth Argument: Similarly, the seventh council does not mention the creed of either the first or second council at all; but simply, after issuing its decree, it adds at the end: “Nothing is to be added or taken away from these. If anyone adds or takes away anything from this faith, let him be anathema.” It is clear, therefore, that it prohibits a contrary and false faith. It does not prohibit the Church from issuing decrees when the matter requires it.

Seventh Argument: Moreover, what “we believe with the heart unto righteousness, we must also confess with the mouth unto salvation.” Otherwise, our faith would be incomplete. Faith must be confessed before men if we desire the promised rewards (as the Savior said, “before our heavenly Father”). But it is necessary to think the truth. Therefore, it is necessary to confess the same. Hence, what must necessarily be believed must also necessarily be confessed, and not only without blame but even necessarily so.

Eighth Argument: Furthermore, in the acts of the fourth council, in the first session, Eutyches first read the Nicene Creed. Then this heretic inferred that the Council of Ephesus decreed that anyone who adds anything beyond this Nicene faith, or thinks or teaches anything, is guilty of the penalties contained therein. But Eusebius, Bishop of Dorylaeum, who constituted himself as the accuser of this heretic out of zeal for the faith, when he heard this, cried out, saying: “There is no such decree, no canon that commands this. He has lied.” The fathers of the council, numbering six hundred and thirty at Chalcedon, heard this, remained silent, and condemned Eutyches, who did not want to know or believe other things which were not explicitly contained in the Nicene Creed; I mean other things in number, not as contradictory or contrary. Hence, they thought that the additions to be prohibited were those contrary and opposite to the truth, not those that are consistent with it. For Christ, after the assumption of the flesh, remains in two natures without confusion, which Eutyches denied, although this is different from the Nicene Creed — not different in meaning but in words — compelling Eutyches to believe this. Therefore, it is clear that the holy doctors did not simply prohibit another faith, but a contrary one.

Ninth Argument: I also remember seeing something similar in the Nomocanon, in the book of the canons of the councils, which our Zonaras explains. In this book, the prohibition of the third council: “After these readings, the holy synod determines,” and so on, is the seventh canon. But before this is another canon of the same council, the sixth, which excludes from communion those who dare to change anything that has been decreed by the synod. In the seventh canon, the prohibition: “After these readings, the holy synod determines that it is not permissible to present another faith,” anathematizes those who transgress this canon and preach another faith. Zonaras, therefore, asks why the holy fathers in the sixth canon only exclude from communion the transgressors, but in the seventh canon, they subject them to anathema. He solves this question with these words: “There is a great difference,” he says, “between contradicting and doubting something. Therefore, those who doubt what has already been rightly established by the fathers are bound by excommunication and deprived of communion, as is prescribed in the sixth canon; but those who contradict it, thinking contrary things, are anathematized,” as the seventh canon or such a prohibition determination wants. Therefore, this commentator also clearly and plainly names “another faith” as contradictory and contrary.

The Tenth Argument: The council held in Trullo, in its first canon, states: “We decree to preserve unaltered and without any innovation the faith handed down to us by the very ministers of the Word, who saw Him with their own eyes, namely the holy apostles, and by the three hundred and eighteen holy fathers assembled at Nicaea.” It subsequently lists all the councils and commands that the faith handed down by all of them should be kept unaltered. Then, in conclusion, it adds: “But if anyone does not hold the aforesaid dogmas of piety, and does not assent to them and think and preach accordingly, but instead tries to oppose them, let him be anathema, according to the canons already established by the aforesaid holy fathers; and let him be expelled and cast out from the Christian fellowship as an alien. For we neither add nor subtract anything whatsoever, following the aforementioned canons.” This canon declares the decree of the third council and others, which prohibit presenting another faith. When it says that if anyone tries to oppose the dogmas of the fathers, let him be anathema according to the canons already established by them, it refers to those canons that prohibit another faith. Therefore, these decrees prohibit a contrary faith. And when they say, “For we neither add nor subtract anything,” they mean in matters of faith, not in the creed. For this synod did not insert the creed into its decree, but by expounding the faith and the dogmas of the holy fathers and all councils, it concludes, “We neither add nor subtract anything.” And the reason is, “Because we follow the aforementioned canons.” So it is clear that when the fathers say, “It is not permissible to add or subtract,” they prohibit not verbal additions and subtractions, but contrary meanings and false sense. Therefore, by this one canon alone, which is not introduced by our reasoning nor commented upon by any private individual, but composed by an entire synod, a whole assembly of fathers who explained their own and similar fathers’ views, the question is most clearly and manifestly resolved for those not wanting to contend. I would have liked to elaborate further. I would have liked either to write down or have at hand all the arguments that were presented to us by the Latins on this question. You would indeed have seen many similar and even more substantial arguments. However, those already mentioned are so clear in deciding this question that they are more than sufficient for anyone who loves the truth and listens to the aforementioned without contention. But they may not satisfy those who wish to argue further. With just one more argument from the Latins added, I will cease speaking further on this matter. We assert that the first, third councils decreed this prohibition, as I said a little earlier, and I explained the reason why we say this: because the second synod added and removed many things from the Nicene Creed, we dare not say that this prohibition was before the second council. If we were to assert that this prohibition existed before the second council, it would necessarily follow one of two things: either to accuse the holy fathers of the second council of transgressing the canons and being under anathema, or, since it is not only absurd but also blasphemous to say this, that the prohibition does not pertain to every verbal addition but prohibits false and contrary meanings from being added. Therefore, we are compelled to say that this prohibition was made after the second synod, not before. If anyone, conversely, shows that this prohibition existed before the second synod, and almost in the same words used by the third council, then one of the two previously mentioned outcomes will follow. And since it is blasphemous to say that the fathers of the second council transgressed the canons, the second outcome remains true: that the prohibition does not mean what our people think but prohibits contrary faith…

.. The Latins showed this to us. For they proved that the first Nicene synod made this prohibition with almost the same words as the third and other councils wrote. They proved it in this way. The Latins are so studious and diligent in all their acts, as your nobility also knows, having experienced their wisdom in many matters, that not only in divine but also in human and civil matters, nothing of ancient deeds or writings escapes them. Therefore, in each city, you will find many records of their ancient deeds in their archives. This is also most carefully preserved in the Catholic Church and other pious places. For many acts of the popes, many letters of the councils, and many canons still exist.

The Eleventh Argument: The Latins presented to us an ancient manuscript containing a letter from Pope Liberius to the blessed Athanasius, the Patriarch of Alexandria, which begins: “From the beginning, we have received so much from the most blessed Peter, the first of the apostles.” In this letter, after a few lines, he mentions receiving a letter from Saint Athanasius and reading it. He then adds: “When we found the faith of the Nicene Council rightly expressed in it, we gave you great thanks; for this, we are not only ready to suffer with you and endure persecution, but also, if necessary, to die for the name of Christ, no matter how weak we are. For as we read, the holy Nicene synod decreed that no one is permitted to present, write, compose, think, or teach another faith, nor to understand or proclaim anything in the faith that is contrary to the decrees of these fathers. Whoever dares to present another faith, or teach, or hand over another creed to those who wish to convert to the way of truth from any heresy, or Judaism, or paganism; if he is a bishop or cleric, let the bishop be deprived of his episcopal dignity and the cleric of his clerical status; if he is a monk or layperson, let him be anathematized.” These things, now unknown to us since the acts of the first council have been lost, were known to Pope Liberius and Saint Athanasius at that time. These words are entirely similar to those of the third council. What shall we say, then, about the second synod and the blessed Gregory Nazianzen, who, presiding over this council as one excelling in wisdom above others, is said to have composed this creed, which the whole Church now uses, changing many things from the Nicene Creed? If this prohibition has the meaning that our people claim, then, alas, the holy fathers and doctors, as well as the fathers of the second council and the blessed Gregory Nazianzen, who was surnamed “Theologian” by excellence, would be considered seducers and deceivers. But far be it from us even to think of such blasphemy. Therefore, neither the first, nor the third, nor any other synod, understands this prohibition as our people interpret it; rather, it prohibits a contrary faith.

Conclusion: It is Permissible to Add the Truth. Therefore, through all these arguments, it has been most clearly proven that it is not prohibited to add the truth to the creed of faith, but rather to declare it. No dogma of truth is contained explicitly or implicitly in the creed and the simple tradition of the apostles. To declare, explain, and add to the creed is not always prohibited nor allowed to everyone, but, compelled by great necessity, and with the judgment of the Church and the authority of the supreme pontiff, it is not only permissible but also necessary.

source: Joseph Gill, the Council of Florence, section on the addition to the creed