Cyprian of Carthage, Eugenius Voulgaris, and "The Three are One"

Two arguments recur in contemporary defenses of the Johannine Comma (the “Heavenly Witnesses” in 1 John 5:7–8): Cyprian’s quotation of “the three are one” and the claim that the masculine grammar of the earthly witnesses requires the heavenly witnesses of v. 7. The latter argument is often associated with a 1780 letter of Eugenios Voulgaris (aka Eugenius Bulgaris).  KJV advocates (the usual defenders of the Comma) object to the idea that Cyprian may have been referring to the spirit, water, and blood as the Father, Son, and Spirit.  What is particularly interesting, however, is that Voulgaris himself interprets the earthly witnesses—the spirit, the blood, and the water—as symbols of the Father, the Son, and the Holy Spirit. 

Usually, the appeal to Voulgaris' letter comes in the form of bolstering an attack on the text of 1 John 5:6-8 as containing (it is alleged) a grammatical solecism in the absence of the interpolation. Students of John's writings, especially the book of Revelation, recognize that John's writing often violates the standards of Attic Greek, but does so intentionally, and with some purpose in these "violations."  Such departures from strict Attic norms are referred to as solecisms, apparently from the negative view that Athenians had of the Greek spoken by the people of Soloi (a Greek colony of Cilicia, in modern-day Turkey) (source).  

Cyprian's Reference to "The Three are One"

On the idea that Cyprian of Carthage may have been quoting 1 John 5:7, the specific quotation is from Cyprian's Treatise 1 (On the Unity of the Church), Section 6 (source), which states:

The spouse of Christ cannot be adulterous; she is uncorrupted and pure. She knows one home; she guards with chaste modesty the sanctity of one couch. She keeps us for God. She appoints the sons whom she has born for the kingdom. Whoever is separated from the Church and is joined to an adulteress, is separated from the promises of the Church; nor can he who forsakes the Church of Christ attain to the rewards of Christ. He is a stranger; he is profane; he is an enemy. He can no longer have God for his Father, who has not the Church for his mother. If any one could escape who was outside the ark of Noah, then he also may escape who shall be outside of the Church. The Lord warns, saying, “He who is not with me is against me, and he who gathereth not with me scattereth.” He who breaks the peace and the concord of Christ, does so in opposition to Christ; he who gathereth elsewhere than in the Church, scatters the Church of Christ. The Lord says, “I and the Father are one;” and again it is written of the Father, and of the Son, and of the Holy Spirit, “And these three are one.” And does any one believe that this unity which thus comes from the divine strength and coheres in celestial sacraments, can be divided in the Church, and can be separated by the parting asunder of opposing wills? He who does not hold this unity does not hold God’s law, does not hold the faith of the Father and the Son, does not hold life and salvation.

Adulterari non potest sponsa Christi, incorrupta est et pudica. Unam domum novit, unius cubiculi sanctitatem casto pudore custodit. Haec nos Deo servat, haec filios regno, quos generavit, assignat. Quisquis ab ecclesia segregatus adulterae iungitur, a promissis ecclesiae separatur, nec perveniet ad Christi praemia, qui relinquit ecclesiam Christi. Alienus est, profanus est, hostis est. Habere iam non potest Deum patrem, qui ecclesiam non habet matrem. Si potuit evadere quisquam, qui extra arcam Noe fuit, et qui extra ecclesiam foris fuerit, evadit. Monet Dominus et dicit: Qui non est mecum, adversus me est, et qui non mecum colligit, spargit. Qui pacem Christi et concordiam rumpit, adversus Christum facit; qui alibi praeter ecclesiam colligit, Christi ecclesiam spargit. Dicit Dominus: Ego et pater unum sumus; et iterum de Patre et Filio et Spiritu sancto scriptum est: Et hi tres unum sunt; et quisquam credit hanc unitatem de divina firmitate venientem, sacramentis coelestibus cohaerentem scindi in ecclesia posse et voluntatum collidentium divortio separari? Hanc unitatem qui non tenet, non tenet Dei legem, non tenet Patris et Filii fidem, vitam non tenet et salutem.

(Latin Text Source and Alternative Translation)(Alternative Source)

I've tried to use text highlighting to emphasize the structure of Cyprian's argument.  In particular, note that Cyprian's last sentence wraps up the rest of this section: 

He who does not hold this unity (i.e., the unity of the church) does not hold God’s law (a reference to the adultery/treason motif), does not hold the faith of the Father and the Son (a reference to the gather/scatter statement and to the "I and the Father we are one" statement), does not hold life and salvation (a reference to the sacraments).  

Cyprian's quotation of 1 John 5:8 "and these three are one" is said to be about the Father, the Son, and the Holy Spirit.  In what way is that?  Some have proposed that it is because John is symbolically referring to the Father, Word, and Spirit as spirit, blood, and water.  Typically, King James defenders balk (or even scoff) at this view.  Before investigating how Comma Defender Voulgaris endorsed such a view, let's consider some other reasonable alternatives. 

Alternatives to the Symbolic View - The Sacramental View

While the explanation of the symbolic interpretation of spirit, blood, and water is the most straightforward explanation of Cyprian's reference that does not require hypothesizing that the Johannine Comma had already been invented, there is another explanation: Cyprian may see the reference to water and blood as references to the sacraments of the Lord's Supper (the body and blood of Christ) and Baptism (water), through which the Spirit works - or perhaps to the Baptism (water) and Death (blood) of Jesus himself.  

Recall that the text says:

1 John 5:5-12 Who is he that overcometh the world, but he that believeth that Jesus is the Son of God? This is he that came by water and blood, even Jesus Christ; not by water only, but by water and blood. And it is the Spirit that beareth witness, because the Spirit is truth. And there are three that bear witness: the Spirit, and the water, and the blood: and these three agree in one. If we receive the witness of men, the witness of God is greater: for this is the witness of God which he hath testified of his Son. And this is the record, that God hath given to us eternal life, and this life is in his Son. He that hath the Son hath life; [and] he that hath not the Son of God hath not life.

You may recall that God's witness to the Son ("my beloved Son") was given at Jesus' own Baptism (Matthew 3:17; Mark 1:11; Luke 3:22).  A weakness of this interpretation of John's epistle is that John is the only evangelist not to mention this particular verbal witness (unless this is the time he is mentioning it).  On the other hand, John could be referring to the inspired witness that John the Baptist gave to Jesus (see, for example, John 3:26) or to the visual witness of the Spirit that John does record (John 1:33).  The strength of this interpretation is that this is a sense in which Jesus "came by water." 

Origen's (185-253) Commentary on John's Gospel, Book VI, Section 26, makes a similar connection between the Baptism of Jesus and 1 John 5:8 (source):

Now, it may very well be that some one not versed in the various aspects of the Saviour may stumble at the interpretation given above of the Jordan; because John says, I baptize with water, but He that comes after me is stronger than I; He shall baptize you with the Holy Spirit. To this we reply that, as the Word of God in His character as something to be drunk is to one set of men water, and to another wine, making glad the heart of man, and to others blood, since it is said, Unless you drink My blood, you have no life in you, and as in His character as food He is variously conceived as living bread or as flesh, so also He, the same person, is baptism of water, and baptism of Holy Spirit and of fire, and to some, also, of blood. It is of His last baptism, as some hold, that He speaks in the words, I have a baptism to be baptized with, and how am I straitened till it be accomplished? And it agrees with this that the disciple John speaks in his Epistle of the Spirit, and the water, and the blood, as being one.

Origen was approximately a contemporary of Cyprian.  

Another interpretation is that "come by water" here refers to Jesus baptizing (or overseeing baptism) as John's gospel records (John 3:22; 3:26; and 4:1-2).  This could then be connected (by Cyprian) with the triune name of God associated with Baptism in Matthew's gospel (Matthew 28:19).

Ambrose, for example, makes a connection of all three witnesses to Christian Baptism.  He does not do so in the way Origen does, but seems to be completely uninfluenced by his view. 

Ambrose (339-397) in On the Holy Spirit, Book I, Chapter 6 (sections 76-77) writes (source):

There are, however, many who, because we are baptized with water and the Spirit, think that there is no difference in the offices of water and the Spirit, and therefore think that they do not differ in nature. Nor do they observe that we are buried in the element of water that we may rise again renewed by the Spirit. For in the water is the representation of death, in the Spirit is the pledge of life, that the body of sin may die through the water, which encloses the body as it were in a kind of tomb, that we, by the power of the Spirit, may be renewed from the death of sin, being born again in God. And so these three witnesses are one, as John said: The water, the blood, and the Spirit. One in the mystery, not in nature. The water, then, is a witness of burial, the blood is a witness of death, the Spirit is a witness of life. If, then, there be any grace in the water, it is not from the nature of water, but from the presence of the Holy Spirit.

Ambrose goes on in Book III, Chapter 10 (Sections 65-68) to write (source):

I ask, however, why, if there be no doubt that we are born again by the Holy Spirit, there should be any doubt that we are born of the Holy Spirit, since the Lord Jesus Himself was both born and born again of the Holy Spirit. And if you confess that He was born of the Holy Spirit, because you are not able to deny it, but deny that He was born again, it is great folly to confess what is peculiar to God, and deny what is common to men. And therefore that is well said to you which was said to the Jews: If I told you earthly things and you believe not, how shall you believe if I tell you heavenly things? And yet we find each passage so written in Greek, that He said not, through the Spirit, but of the Spirit. For it stands thus: ἀμήν, ἀμήν, λέγω σοι, ἐὰν μή τις γεννηθῇ ἐξ ὓδατος και Πνεύματος, that is, of water and the Spirit. Therefore, since one ought not to doubt that that which is born of the Spirit is written of the Holy Spirit; there is no doubt but that the Holy Spirit also is God, according to that which is written, the Spirit is God.  But the same Evangelist, that he might make it plain that he wrote this concerning the Holy Spirit, says elsewhere: Jesus Christ came by water and blood, not in the water only, but by water and blood. And the Spirit bears witness, because the Spirit is truth; for there are three witnesses, the Spirit, the water, and the blood; and these three are one. Hear how they are witnesses: The Spirit renews the mind, the water is serviceable for the laver, and the blood refers to the price. For the Spirit made us children by adoption, the water of the sacred Font washed us, the blood of the Lord redeemed us. So we obtain one invisible and one visible testimony in a spiritual sacrament, for the Spirit Himself bears witness to our spirit. Though the fullness of the sacrament be in each, yet there is a distinction of office; so where there is distinction of office, there certainly is not equality of witness.

Notice the sacramental connection, as well as this explicit and positive testimony against the Comma, by quoting from before its insertion point to after without including it, particularly when it would have suited Ambrose's argument if it were known to him.

Consider the way that Ambrose makes a Trinitarian connection to the passage in On the Mysteries, Chapter 4 (Section 20)(source):

Therefore read that the three witnesses in baptism, the water, the blood, and the Spirit, are one, for if you take away one of these, the Sacrament of Baptism does not exist. For what is water without the cross of Christ? A common element, without any sacramental effect. Nor, again, is there the Sacrament of Regeneration without water: For except a man be born again of water and of the Spirit, he cannot enter into the kingdom of God. Now, even the catechumen believes in the cross of the Lord Jesus, wherewith he too is signed; but unless he be baptized in the Name of the Father, and of the Son, and of the Holy Spirit, he cannot receive remission of sins nor gain the gift of spiritual grace.

In another place (Concerning Virginity, Book III, Chapter 5, section 22, link to source), Ambrose does not make an explicit citation of 1 John 5:7-8, but nevertheless makes a similar connection:

And since I have inserted a clause in which mention is made of the Lord's Body, lest any one should be troubled at reading that the Lord took a body of pain, let him remember that the Lord grieved and wept over the death of Lazarus, and was wounded in His passion, and that from the wound there went forth blood and water, and that He gave up His Spirit. Water for washing, Blood for drink, the Spirit for His rising again. For Christ alone is to us hope, faith, and love— hope in His resurrection, faith in the laver, and love in the sacrament.

The Spear Piercing - Double Baptism View

Why go down the sacramental path at all?  Partly this is because of the slight obscurity of what it means for Jesus to "come by water" or by both water and blood.  Other interpretations have suggested that Jesus was born of water in the sense of being naturally born from his mother's womb (based on an interpretation of John 3:5).  Another Biblical mention of water and blood is in John 19:34 (and Matthew 27:49b in more Greek manuscripts than have the TR comma), where blood and water flowed out of Jesus' side upon His side being pierced with a spear (Rufinus (344-411) in his Commentary on the Apostles' Creed, section 23, refers to both this blood and water from the spear-piercing as baptism - link to source).

Considering that John's gospel just summarily says that the Word was made Flesh, and does not provide any infancy narrative, the "came by water" as relating to his birth seems less likely as a viable explanation.  On the other hand, there is mention of testimony associated with piercing of Jesus' side:

John 19:31-37 The Jews therefore, because it was the preparation, that the bodies should not remain upon the cross on the sabbath day, (for that sabbath day was an high day,) besought Pilate that their legs might be broken, and [that] they might be taken away. Then came the soldiers, and brake the legs of the first, and of the other which was crucified with him. But when they came to Jesus, and saw that he was dead already, they brake not his legs: But one of the soldiers with a spear pierced his side, and forthwith came there out blood and water. And he that saw [it] bare record, and his record is true: and he knoweth that he saith true, that ye might believe. For these things were done, that the scripture should be fulfilled, A bone of him shall not be broken. And again another scripture saith, They shall look on him whom they pierced.  

Here, the record of the water and blood is supported by the Evangelist, but also aligned with the inspired Old Testament Scriptures.

Tertullian (155 - 220), in On Baptism, Chapter 16, connects the spear-piercing with Baptism (source):

We have indeed, likewise, a second font, (itself withal one with the former,) of blood, to wit; concerning which the Lord said, I have to be baptized with a baptism, when He had been baptized already. For He had come by means of water and blood,  just as John has written; that He might be baptized by the water, glorified by the blood; to make us, in like manner, called by water, chosen by blood. These two baptisms He sent out from the wound in His pierced side, in order that they who believed in His blood might be bathed with the water; they who had been bathed in the water might likewise drink the blood. This is the baptism which both stands in lieu of the fontal bathing when that has not been received, and restores it when lost.

An anonymous author (writing in the third or fourth century) offers these thoughts in On Re-Baptism, sections 14, 15, 18, and 19 (source):

14. And even to this point the whole of that heretical baptism may be amended, after the intervention of some space of time, if a man should survive and amend his faith, as our God, in the Gospel according to Luke, spoke to His disciples, saying, But I have another baptism to be baptized with. Also according to Mark He said, with the same purpose, to the sons of Zebedee: Are you able to drink of the cup which I drink of, or to be baptized with the baptism wherewith I am baptized?  Because He knew that those men had to be baptized not only with water, but also in their own blood; so that, as well baptized in this baptism only, they might attain the sound faith and the simple love of the laver, and, baptized in both ways, they might in like manner to the same extent attain the baptism of salvation and glory. For what was said by the Lord, I have another baptism to be baptized with, signifies in this place not a second baptism, as if there were two baptisms, but demonstrates that there is moreover a baptism of another kind given to us, concurring to the same salvation. And it was fitting that both these kinds should first of all be initiated and sanctified by our Lord Himself, so that either one of the two or both kinds might afford to us this one twofold saving and glorifying baptism; and certain ways of the one baptism might so be laid open to us, that at times some one of them might be wanting without mischief, even as in the case of martyrs that hear the word, the baptism of water is wanting without evil; and yet we are certain that these, if they had any indulgence, would also be used to be baptized with water. And also to those who are made lawful believers, the baptism of their own blood is wanting without mischief, because, being baptized in the name of Christ, they have been redeemed with the most precious blood of the Lord; since both of these rivers of the baptism of the Lord proceed out of one and the same fountain, that every one who thirsts may come and drink, as says the Scripture, From his belly flowed rivers of living water;  which rivers were manifested first of all in the Lord's passion, when from His side, pierced by the soldier's spear, flowed blood and water, so that the one side of the same person emitted two rivers of a different kind, that whosoever should believe and drink of both rivers might be filled with the Holy Spirit. For, speaking of these rivers, the Lord set this forth, signifying the Holy Spirit whom they should receive who should believe in Him: But the Spirit was not yet given, because Jesus was not yet glorified. And when He thus said how baptism might be produced, which the apostle declares to be one, it is assuredly manifest on that principle that there are different kinds of one and the same baptism that flow from one wound into water and blood; since there are there two baptisms of water of which we have spoken, that is, of one and the same kind, although the baptism of each kind ought to be one, as we have more fully spoken.

15. And since we seem to have divided all spiritual baptism in a threefold manner, let us come also to the proof of the statement proposed, that we may not appear to have done this of our own judgment, and with rashness. For John says of our Lord in his epistle, teaching us: This is He who came by water and blood, Jesus Christ; not by water only, but by water and blood: and it is the Spirit that bears witness, because the Spirit is truth. For three bear witness, the Spirit, and the water, and the blood: and these three are one;  — that we may gather from these words both that water is wont to confer the Spirit, and that men's own blood is wont to confer the Spirit, and that the Spirit Himself also is wont to confer the Spirit. For since water is poured forth even as blood, the Spirit also was poured out by the Lord upon all who believed. Assuredly both in water, and none the less in their own blood, and then especially in the Holy Spirit, men may be baptized. 

...

18. ...  From all which things it is shown that hearts are purified by faith, but that souls are washed by the Spirit; further, also, that bodies are washed by water, and moreover that by blood we may more readily attain at once to the rewards of salvation.

19. I think that we have fully followed out the announcement of John the Baptist, whence we began our discourse, when he said to the Jews, I indeed baptize you with water unto repentance; but He who comes after me is greater than I, whose shoe's latchet I am not worthy to unloose: He shall baptize you with the Holy Ghost, and with fire. Moreover, I think also that we have not unsuitably set in order the teaching of the Apostle John, who says that three bear witness, the Spirit, and the water, and the blood; and these three are one. And, unless I am mistaken, we have also explained what our Lord says: John indeed baptized with water, but you shall be baptized with the Holy Ghost. Moreover, I think that we have given no weak reason as the cause of the custom. Let us have a care, although we do that in a subsequent place, that none may think that we are stirring up the present debate on a single article; although this custom even alone ought, among men who have the fear of God, and are lowly, to maintain a chief place.

I don't adopt this author's views (cf. Basil (330-379), On the Holy Spirit, Chapter 15, Section 36 - link to source), but merely offer them as being roughly contemporaneous with Cyprian, testifying to a sacrament-related (and even spear-related) view of the text, as well as providing an explicit testimony to the non-interpolation of the Johannine Comma.  Incidentally, Cyprian himself referred to a baptism of blood, referring to the death of the person himself in his Epistle 72, at sections 21-22 (link to source).

Leo's Life of Christ View 

Leo the Great (391– 461) makes a similar reference to both the spear-piercing and 1 John 5:8 in his famous "Tome of Leo," which was received by the Council of Chalcedon of 451 (often referred to as the 4th Ecumenical Council)(source), which is a clear positive testimony against the Comma:

If therefore he receives the Christian faith, and does not turn away his ears from the preaching of the Gospel: let him see what was the nature that hung pierced with nails on the wooden cross, and, when the side of the Crucified was opened by the soldier's spear, let him understand whence it was that blood and water flowed, that the Church of God might be watered from the font and from the cup. Let him hear also the blessed Apostle Peter, proclaiming that the sanctification of the Spirit takes place through the sprinkling of Christ's blood. And let him not read cursorily the same Apostle's words when he says, Knowing that not with corruptible things, such as silver and gold, have you been redeemed from your vain manner of life which is part of your fathers' tradition, but with the precious blood of Jesus Christ as of a lamb without spot and blemish. Let him not resist too the witness of the blessed Apostle John, who says: and the blood of Jesus the Son of God cleanses us from all sin. And again: this is the victory which overcomes the world, our faith. And who is He that overcomes the world save He that believes that Jesus is the Son of God. This is He that came by water and blood, Jesus Christ: not by water only, but by water and blood. And it is the Spirit that testifies, because the Spirit is the truth, because there are three that bear witness, the Spirit, the water and the blood, and the three are one.  The Spirit, that is, of sanctification, and the blood of redemption, and the water of baptism: because the three are one, and remain undivided, and none of them is separated from this connection; because the Catholic Church lives and progresses by this faith, so that in Christ Jesus neither the manhood without the true Godhead nor the Godhead without the true manhood is believed in.

But - of course - the primary reason to go down the sacramental path is because of Cyprian's statement that God's unity "coheres in celestial sacraments" (sacramentis coelestibus cohaerentem).  That's seen in both the unity of the Sacrament of the Lord's table, in which we consume the one loaf that we are (1 Corinthians 10:17; cf. Cyprian, Epistle 62, section 13 - link to source), and the unity of the Sacrament of Baptism, in which "one baptism" (Ephesians 4:5) we are baptized in the name of the Father, Son, and Holy Ghost (Matthew 28:19).  Connecting the death of Christ and Baptism to church unity has Scriptural precedent -- Paul writes: "Is Christ divided? was Paul crucified for you? or were ye baptized in the name of Paul?" (1 Corinthians 1:13)

You only have to read the rest of Cyprian's treatise (available here) to get the same sense of Cyprian's willingness to follow Paul's point and also to develop the same themes from Scriptural passages that are not necessarily directly about the point being considered.  For example, in the very next section of the treatise, Cyprian argues for the necessary unity of the Church from Jesus' garment remaining undivided (e.g., "By the sacrament and sign of His garment, He has declared the unity of the Church.").

Incidentally, this broader use of the term "sacrament" suggests that Cyprian may just be speaking symbolically, not necessarily referring strictly to the two Sacraments of the New Covenant.

Cyprian in Context - the Unity of the Church 

One must also consider Cyprian's point in citing 1 John 5:8.  Was it to establish the unity of essence of the Triune persons?  The argument seems to be about unity of purpose and mission, a sense that fits well with his quotation of John 10:30 ("I and my Father are one"), and does not require Cyprian to be taking John out of context there.  In context "the three are one" relates to the unity of agreement of the three bearing witness, not their unity of essence.  Moreover, in context, that unity of testimonial agreement serves the purpose of bringing life through faith, which is the main point of the church in Cyprian's view as well.

Likewise, while it is not perfectly clear that Spirit points to Father, Blood points to the Son, and Water points to the Holy Spirit, it is certainly easy to see how someone who sees the undivided garment of Christ as being a sacrament of Christian unity could see the context of 1 John 5:8 as pointing in this direction, for John writes: "And there are three that bear witness: the Spirit, and the water, and the blood: and these three agree in one. If we receive the witness of men, the witness of God is greater." (1 John 5:7-9).  It would be easy for Cyprian to see "the witness of God" and "the three are one" and to infer that Spirit, water, and blood refer to the persons of the Most Holy Trinity.

Gregory Nazianzen: Trinitarian with a Non-Trinitarian Interpretation 

Gregory Nazianzen (329-390), however, takes a view that John is not speaking about the Trinity in his Fifth Theological Oration (Oration 31) (source):

XIX. But to my mind, he says, those things are said to be connumerated and of the same essence of which the names also correspond, as Three Men, or Three gods, but not Three this and that. What does this concession amount to? It is suitable to one laying down the law as to names, not to one who is asserting the truth. For I also will assert that Peter and James and John are not three or consubstantial, so long as I cannot say Three Peters, or Three Jameses, or Three Johns; for what you have reserved for common names we demand also for proper names, in accordance with your arrangement; or else you will be unfair in not conceding to others what you assume for yourself. What about John then, when in his Catholic Epistle he says that there are Three that bear witness, the Spirit and the Water and the Blood? Do you think he is talking nonsense? First, because he has ventured to reckon under one numeral things which are not consubstantial, though you say this ought to be done only in the case of things which are consubstantial. For who would assert that these are consubstantial? Secondly, because he has not been consistent in the way he has happened upon his terms; for after using Three in the masculine gender he adds three words which are neuter, contrary to the definitions and laws which you and your grammarians have laid down. For what is the difference between putting a masculine Three first, and then adding One and One and One in the neuter, or after a masculine One and One and One to use the Three not in the masculine but in the neuter, which you yourself disclaim in the case of Deity? What have you to say about the Crab, which may mean either an animal, or an instrument, or a constellation? And what about the Dog, now terrestrial, now aquatic, now celestial? Do you not see that three crabs or dogs are spoken of? Why of course it is so. Well then, are they therefore of one substance? None but a fool would say that. So you see how completely your argument from connumeration has broken down, and is refuted by all these instances. For if things that are of one substance are not always counted under one numeral, and things not of one substance are thus counted, and the pronunciation of the name once for all is used in both cases, what advantage do you gain towards your doctrine?

At some point, our KJV advocacy friends throw up their hands and exclaim that we are being wholly unreasonable to make a linkage between the Spirit, Water, and Blood and the persons of the Trinity - and following Leo or Gregory on the interpretation of the text, we may agree with them about the right sense.  

On the other hand, I would like them to consider their own champion on the grammatical argument (one who stands opposed to Gregory Nazianzen, whose text did not include the Comma): because that's exactly how their champion, Voulgaris, interprets the text!

I'm not suggesting that Voulgaris is infallible, or even right - surely Gregory Nazianzen's and Leo the Great's takes on the text are each better than Cyprian's.  However, considering that Voulgaris is one of the go-to sources for the grammatical argument, KJV advocates ought not lightly set aside his interpretation of the text.  Even if they disagree with it, saying it is wholly unreasonable - or something that only opponents of the Comma would suggest - seems like it is hereby demonstrated to be untenable.

In particular, Voulgaris argues that the heavenly witnesses are what the earthly witnesses symbolize. He made these claims long before the boogey-men, Westcott and Hort were on the scene.  He also made these claims in defense of the verse against being an interpolation. See the details of his claims in the letter that follows. 

My (amateur) Translation of the Text of Voulgaris 

In some places, I've slightly departed from the accents/breathings provided in the printed text (see my transcription of the printed text below). First, I provide a translation of the Latin of the document, and then I offer a translation of the Greek portions. 

This alone I could add at present, which by no one (that I know) has hitherto been observed. So far indeed is it from being the case that that passage crept in through interpolation, that not even the eighth verse, which follows, would stand, unless the seventh verse, about which the matter is, preceded.

For what in the Latin version is rightly expressed by the masculine gender of speech, that, in the original Greek text itself, the preceding verse not being presupposed, would by no means stand, except with a certain violence of diction and through a most manifest solecism. For since

τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα [1]

are nouns of the neuter gender, in what way will that which immediately precedes agree with them:

Τρεῖς εἰσιν οἱ μαρτυροῦντες [2];

and that which immediately follows:

Καὶ οὗτοι οἱ τρεῖς κ. τ. λ. [3]

That masculine nouns, indeed, and feminine ones are construed with adjectives and pronouns expressed in the neuter gender, regard being had to

τὰ πράγματα [4],

is certainly a peculiar genius of our language, most well known to all who know it; but that, conversely, neuter substantive nouns are indicated by masculine or feminine adjectives or pronouns, no one would say.

Further, here in the eighth verse we read thus:

Τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῇ γῇ, τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα· καὶ οἱ τρεῖς εἰς τὸ ἓν εἰσι. [5]

But would not, I ask, the natural and proper expression here rather be:

Τρία εἰσι τὰ μαρτυροῦντα ἐν τῇ γῇ, τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα· καὶ τὰ τρία εἰς τὸ ἓν εἰσιν? [6]

Yet that is written, not this. What other account, therefore, can be brought forward for the occurrence of this

ἀκαταλληλίας [7],

except solely the expression of the preceding seventh verse, which through this immediately following eighth verse is symbolically explained and plainly repeated, an allusion having been made to that which had preceded?

The three, therefore, who bear testimony in heaven are first placed in the seventh verse:

Τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῷ οὐρανῷ, ὁ Πατὴρ, ὁ Λόγος, καὶ τὸ ἅγιον Πνεῦμα· καὶ οὗτοι οἱ τρεῖς ἓν εἰσι. [8]

Then, however, immediately brought forward, the very same witnesses, insofar as they also confirm the same testimony on earth, through these three symbols in the eighth verse:

Καὶ τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῇ γῇ, τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα· καὶ οἱ τρεῖς εἰς τὸ ἓν εἰσι. [9]

As if our Evangelist were saying:

Οἱ αὐτοὶ ἐκεῖνοι οἱ ἐν τῷ οὐρανῷ μαρτυροῦντες [10]

(which is sufficiently indicated by the particle καὶ [11], whose force in the present passage is not simply copulative, but plainly identificative)

περὶ ὧν ἐν τῷ ἀνωτέρῳ ἐδαφίῳ εἴρηται· δηλαδὴ ὁ Πατὴρ ὁ Λόγος καὶ τὸ Πνεῦμα· οἱ αὐτοὶ μαρτυροῦντες εἰσι καὶ ἐν τῇ γῇ, δι’ ὧν ἡμῖν συμβόλων ἀπεκαλύφθησαν· ταῦτα δὲ τὰ σύμβολά ἐστι τὸ πνεῦμα, δι’ οὗ δηλοῦται ὁ Πατήρ· τὸ αἷμα, δι’ οὗ ὁ Υἱός· τὸ ὕδωρ, δι’ οὗ τὸ Πνεῦμα τὸ ἅγιον. Καὶ οἱ τρεῖς οὗτοι, οἵτινες ἀνωτέρω μὲν ἀνακεκαλυμμένως δι’ αὐτῶν τῶν θεαρχικῶν ὀνομάτων, ἐν τῷ οὐρανῷ μαρτυροῦντες παρίστανται οἱ αὐτοὶ ἐν τῇ γῇ διὰ τῆς ἐν τῇ οἰκονομίᾳ μνήσεως, συμβολικῶς ἐπαναλαμβανόμενοι· οἱ τρεῖς οὗτοι εἰς τὸ ἓν εἰσι. [12]

But oh! I have undertaken a pitcher, not an amphora!

At Poltava, on the 10th day of December, 1780.

And my (again amateur) translation of the Greek portions:

1. τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα

the spirit and the water and the blood

2. Τρεῖς εἰσιν οἱ μαρτυροῦντες

Three [masc.] are the ones [masc.] bearing witness.

3. Καὶ οὗτοι οἱ τρεῖς κ. τ. λ.

And these three, etc.

4. τὰ πράγματα

the things [i.e., the nature of those things]

5. Τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῇ γῇ,

Three [masc.] are the ones [masc.] bearing witness on the earth,

τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα·

the spirit and the water and the blood;

καὶ οἱ τρεῖς εἰς τὸ ἓν εἰσι.

and the three are unto the one.

6. Τρία εἰσι τὰ μαρτυροῦντα ἐν τῇ γῇ,

Three [neut.] are the things [neut.] bearing witness on the earth,

τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα·

the spirit and the water and the blood;

καὶ τὰ τρία εἰς τὸ ἓν εἰσιν?

and the three [neut.] are unto the one?

7. ἀκαταλληλίας

of incongruity / of lack of agreement

8. Τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῷ οὐρανῷ,

Three [masc.] are the ones [masc.] bearing witness in heaven,

ὁ Πατὴρ, ὁ Λόγος, καὶ τὸ ἅγιον Πνεῦμα·

the Father, the Word, and the Holy Spirit;

καὶ οὗτοι οἱ τρεῖς ἓν εἰσι.

and these three are one.

9. Καὶ τρεῖς εἰσιν οἱ μαρτυροῦντες ἐν τῇ γῇ,

And three [masc.] are the ones [masc.] bearing witness on the earth,

τὸ πνεῦμα καὶ τὸ ὕδωρ καὶ τὸ αἷμα·

the spirit and the water and the blood;

καὶ οἱ τρεῖς εἰς τὸ ἓν εἰσι.

and the three are unto the one.

10. Οἱ αὐτοὶ ἐκεῖνοι οἱ ἐν τῷ οὐρανῷ μαρτυροῦντες

Those very same ones, the ones bearing witness in heaven

11. καὶ

Most commonly, this word means "and" or "also," but here Voulgaris is saying it has the sense of "namely" 

12. περὶ ὧν ἐν τῷ ἀνωτέρῳ ἐδαφίῳ εἴρηται·

concerning whom it has been said in the passage above;

δηλαδὴ ὁ Πατὴρ ὁ Λόγος καὶ τὸ Πνεῦμα·

namely, the Father, the Word, and the Spirit;

οἱ αὐτοὶ μαρτυροῦντες εἰσι καὶ ἐν τῇ γῇ,

the same ones are bearing witness also on the earth,

δι’ ὧν ἡμῖν συμβόλων ἀπεκαλύφθησαν·

through which symbols they were revealed to us;

ταῦτα δὲ τὰ σύμβολά ἐστι τὸ πνεῦμα, δι’ οὗ δηλοῦται ὁ Πατήρ·

and these symbols are the spirit, through which the Father is indicated;

τὸ αἷμα, δι’ οὗ ὁ Υἱός·

the blood, through which the Son [is indicated];

τὸ ὕδωρ, δι’ οὗ τὸ Πνεῦμα τὸ ἅγιον.

the water, through which the Holy Spirit [is indicated].

Καὶ οἱ τρεῖς οὗτοι, οἵτινες ἀνωτέρω μὲν

And these three, who above indeed,

ἀνακεκαλυμμένως δι’ αὐτῶν τῶν θεαρχικῶν ὀνομάτων,

in an unveiled manner, through the thearchic names themselves,

ἐν τῷ οὐρανῷ μαρτυροῦντες παρίστανται

are presented as bearing witness in heaven,

οἱ αὐτοὶ ἐν τῇ γῇ

the same [are presented] on the earth,

διὰ τῆς ἐν τῇ οἰκονομίᾳ μνήσεως,

through the mention in the economy,

συμβολικῶς ἐπαναλαμβανόμενοι·

being repeated symbolically;

οἱ τρεῖς οὗτοι εἰς τὸ ἓν εἰσι.

these three are unto the one.

Source Text (trying to stay faithful to the printed text)

Hoc ego tantummodo in præsenti addere possem, quod a nemine (quod sciam) hactenùs observatum. Tantum scilicet abesse, per interpolationem locum illum surrepsisse, ut ne quidem versus octavus, qui sequitur, staret, nisi versus septimus præcederet, de quo agitur. Quod enim in versione Latina rectè exprimitur masculino sermonis genere, id in ipso textu Græco originali, non præsupposito superiore versiculo, haud planè consisteret, nisi cum violentia quadam dictionis, ac per solœcismum patentissimum. Cum etenim το πνευμα και το ὑδωρ και το αἱμα nomina neutrius generis sunt, qua ratione concordabit cum iis, quod immediatè præcedit: Τρεις εισιν οἱ μαρτυρουντες; et quod illico sequitur: Και οὑτοι οἱ τρεις κ. τ. λ.  Masculina equidem nomina, et fœminina, nominibus adjectivis, pronominibusque in neutro genere expressis construi, respectu habito ad τα πραγματα, id sane linguæ nostræ peculiare genium esse omnibus eam callentibus notissimum est; sed quod etiam reciprocè neutra nomina substantiva adjectivis vel pronominibus masculinis aut fœmininis indicentur, nemo dixerit. Porro hic versu octavo sic legimus: Τρεις εισιν οἱ μαρτυρουντες εν τῃ γῃ, το πνευμα και το ὑδωρ και το αἱμα· και οἱ τρεις εις το ἓν εισι. Sed nonne quæso dictio naturalis hic et propria potius esset: Τρια εισι τα μαρτυρουντα εν τῃ γῃ, το πνευμα και το ὑδωρ και το αἱμα· και τα τρια εις το ἓν εισιν? At illud tamen est scriptum non hoc. Quæ igitur alia ratio occurrentis istius ακαταλληλιας afferri potest, nisi sola præcedentis versus septimi expressio, quæ per hunc immediate sequentem versum octavum, symbolicè explicatur et planè replicatur, allusione facta ad id, quod præcesserat? Tres, igitur, qui in cœlo testimonium perhibent, primo positi sunt versu septimo: Τρεις εισιν οἱ μαρτυρουντες εν τῳ ουρανῳ, ὁ Πατηρ, ὁ Λογος, και το ἁγιον Πνευμα· και οὑτοι οἱ τρεις ἓν εισι. Deinceps vero immediatè adducti, iidem ipsi testes, quatenus in terra etiam testimonium idem confirment, per tria hæc symbola versu octavo: Και τρεις εισιν οἱ μαρτυρουντες εν τῃ γῃ, το πνευμα και το ὑδωρ και το αἱμα· και οἱ τρεις εις το ἓν εισιν. Ac si diceret Evangelista noster: Οἱ αυτοι εκεινοι οἱ εν τῳ ουρανῳ μαρτυρουντες (quod satis indicatur per particulam και, cujus vis in præsenti non simpliciter copulativa est, sed planè identifica) περι ὡν εν τῳ ανωτερῳ εδαφιῳ ειρηται· δηλαδη ὁ Πατηρ ὁ Λογος και το Πνευμα· οἱ αυτοι μαρτυρουντες εισι και εν τῃ γῃ, δι’ ὡν ἡμιν συμβολων απεκαλυφθησαν· ταυτα δε τα συμβολα εστι το πνευμα, δι’ ου δηλουται ὁ Πατηρ· το αἱμα, δι’ ου ὁ Υἱος· το ὑδωρ, δι’ ου το Πνευμα το ἁγιον. Και οἱ τρεις οὑτοι, οἱτινες ανωτερῳ μεν ανακεκαλυμμενως δι’ αυτων των θεαρχικων ονοματων, εν τῳ ουρανῳ μαρτυρουντες παριστανται οἱ αὐτοι εν τῃ γῃ δια της εν τῃ οικονομιᾳ μνησεως, συμβολικως επαναλαμβανομενοι· οἱ τρεις οὑτοι εις το ἓν εισι. Sed ohe! urceum institui, non amphoram!

Poltaviæ, ad d. 10 Decemb. 1780