St. Isidore and the Filioque

Doctrine and Creed

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INTRODUCTION

St. Isidore is one of the most interesting Fathers of the early Church, a person favorite of many theologians in the Medieval era and a personal favorite of mine.

St. Isidore’s encyclopedic treatment of issues of theology and natural science alike will always be one of the most impressive feats in the history of mankind.

Due to the encyclopedic nature of his work, he can be trusted as a thorough and clear guide on the matters that he discusses. One issue that is of particular interest is the issue of the Filioque. In his etymologies, he has a section on God, where he discusses the Unity and Trinity of God. Under the title De Spiritu Sancto he immediately begins by writing

The Holy Spirit is proclaimed to be God because it proceeds from the Father and the Son, and has God’s substance, for no other thing could proceed from the Father than what is itself the Father. (VII.iii.1)

Further,

Between the Son who is born and the Holy Spirit who proceeds is this distinction, that the Son is born from one, the Holy Spirit proceeds from both. (ibid., 8)

Then, under the title De Trinitate, he writes

Only the Father is not derived from another; therefore he is called Unbegotten (Ingenitus). Only the Son is born of the Father; therefore he is called Begotten (Genitus). Only the Holy Spirit proceeds from the Father and the Son; therefore it alone is referred to as ‘the Spirit of both the others.’ (Ibid., iv.4)

These are clear enough and there are other comments made in these sections which imply the same exact doctrine. Yet, this is neither the only witness to the doctrine of the Filioque from St. Isidore, nor the clearest.

The clearest instance is from a letter that was written to “General Claudius,” the sixth in his corpus of letters. My friend Joshua Charles has provided a good overview of its teaching on the papacy here.

This is already quite clear, but the general subject of the letter (for which he invoked the authority of the Roman Church) was in order to demonstrate NOT ONLY that the Filioque is true BUT ALSO that it can be licitly added to the Creed if the proper authorities concede.

THE LETTER OF ST. ISIDORE

Likewise, you took care to make known to me the objection of some Greeks that in the synod of Nicea and Constantinople it is said that it was prohibited under pain of anathema in the Apostles’ Creed and in that of holy Athanasius to take away or add something concerning the Catholic faith; and so some of the Greeks boldly strive to reprehend the Romans because in the profession of holy faith they sing with heart and mouth to God: Who proceeds from the Father and the Son, although in the aforementioned councils it was stated: Who proceeds from the Father, and the Holy Roman Church approves and believes that the Holy Spirit proceeds from the Father and the Son.

If this above-mentioned prohibition is considered subtly and rightly, all ambiguity will be removed; for when it prohibited one to add or take away something, it meant a different thing, with which opinion the following statement of the Apostle agrees: If any man preaches any other thing to you besides that which you have received from us, let him be accursed (Gal. 1:9). And the Apostle John says: If anyone comes to you, bringing another doctrine, do not receive him and do not greet him (2 Jn. 1:10). When he said another doctrine, warning against heresy, without ambiguity he wished to point out to us the difference of doctrine.

Indeed, the apostles, martyrs, and orthodox teachers of the Church preached many other things; but as they are not contradictory, an apostolic prohibition of this kind is not considered to be contradictory because they are tending to one end of truth. Thus since it is known that the same judgment concerns similar things, it is clear and far from doubt that prohibitions of the aforesaid opinions should be accepted concerning the difference of heresies.

But let us show clearly by evidence of Holy Scripture that the Holy Spirit belongs to the Father and to the Son and is sent from the Father and from the Son and proceeds from both. The words of the Apostle are these: If his spirit, which aroused Jesus from the dead, dwells in you, etc. (Col. 2:12). And elsewhere: God sent the spirit of his Son into our hearts (Gal. 4:6). And so, it is manifestly obvious by the words of the Apostle that the Holy Spirit belongs to God the Father raising from death, and to God the raised Son, who are not three gods. One is to be believed and worshipped, as Moses testifies: Hear O Israel, the Lord your God is one God (Deut. 6:4).

The Lord says in the Gospel that the Holy Spirit is sent by the Father, saying: The Comforter, which is the Holy Spirit, whom the Father will send in my name, will teach you all things (Jn. 14:26). And the same truth says that he is sent by the Son: When the Comforter comes, whom I shall send to you from the Father (Jn. 15:26). Thus it is declared fully in these statements that the Holy Spirit is sent by the Father and by the Son. The Holy Spirit is certainly shown to come from the Father, when it is said: The Spirit of truth, which proceeds from the Father (Jn. 15:26); but from the Son, when he breathed after his resurrection and said to his disciples: Receive the Holy Spirit (Jn. 20:22).

Isaiah also says in the person of the Father: The Spirit will depart from my countenance (Is. 57:56 [LXX]). The only-begotten is the word of God the Father and his face, for a man is recognized by us by his face, and God the Father was known to the world through his Son; whence the Son says: Father, I have manifested your name to the men whom you gave to me (Jn. 17:6). And this: I have made known your name to them and I shall make it known (Jn. 17:26). We can adduce more statements to prove these things more fully, but perhaps many examples will not benefit the salvation of one to whom these are not sufficient since the natural man does not perceive those things which are of the Spirit of God (I Cor. 2:14), thinking that what is said is stupid. Because this certainly results from contemptible ignorance, being ignorant, he will be ignored.

But when in speaking we distinguish the persons of the Holy Trinity, we should greatly take care that we do not appear to divide the individual and most simple essence of one God. But if we do not understand the meaning of that inexpressible begetting by the Father, that birth, being begotten, or death of the Son, which cannot be appraised, or that incomprehensible being sent or procession of the Holy Spirit from the Father and the Son and other things of this kind which are said about the difference of the persons, let us take them on faith so that we may deserve to be saved forever.

And so, with as much brevity as I could, I have answered your questions. But concerning your statement that you have heretics with whom you constantly disagree, and whom you desire to recall to the Catholic faith, I praise your zeal but reprehend your audacity. For the divine Scripture says: Whoever has touched pitch will be defiled by it (Ecc. 13:1). Thus beware, beloved son, lest because God has made you victorious with triumphal victories and strength of arms over fallen enemies, you succumb, conquered ignominiously by heretical persuasions; for while you labor to rescue them from the error of death, they themselves stay awake to submerge you in the abyss of error; from their conversation or solace I advice every Christian to abstain under the threat of divine judgment, as if from lethal poison, unless he is proven in divine precepts by experience of works and is erudite in the Holy Scriptures.

Thus I beseech in the presence of God, I advise, and as much as I can, I order and exhort that you drive them from yourself as quickly as possible, exercising the zeal of God’s law, unless they have professed the Catholic truth, and that you do not delay to send in writing to me their words and objections. With God as a witness, I dearly embrace the fraternity of your beloved self in the bosom of Jesus Christ; and I shall indicate individual things, as far as God may grant it, for the salvation of your soul and the health of your body, supporting them with holy authorities, so that false-hood may yield to truth and the glory of the Church of Christ may be strengthened and grow. Remember our common teacher Leander, and imitate his faith and doctrine in accordance with your strength so that you may be able to enjoy good at the present and obtain a share of celestial goods in the future. Amen. Pray for me. May the Lord grant that wholeness of mind, body, faith, and honor may be preserved by you and that I may deserve to see you in the future, my lord and dearest son.