Tractatus de Deo Trino secundum personas

« In the doctrine of s. John, when the connection has been set forth in I. Io. V. 6-9. between the testimony of the Spirit for Christ as God and as man v. 6, between the testimony of the three on earth for the true humanity of Christ v. 8, and between the testimony of the three in heaven, the Father, the Word and the Holy Spirit, who are three one v. 7; from this very passage the unity of three really distinct persons according to the divine essence is demonstrated ».

I. We shall speak first of the connection of verse 6. with the clauses 7°. and 8°. For this, moreover, it is necessary to investigate the scope which John had set before himself in the epistle, and further to determine the sense both of the testimony and of the words water and blood and spirit, which are treated in that v. 6. From this, indeed, the signification of the witnesses of v. 8. is also to be understood, since there too three witnesses are named, the spirit, the water and the blood.

The principal scope of John the Apostle, just as in his Gospel so also in this epistle, as it were an introduction to the Gospel, is this, that he teach and preach, « that Jesus is the Christ, the Son of God » Io. XX. 31, which he declares most openly immediately at the beginning of the epistle just as at the beginning of the Gospel, and repeats and inculcates everywhere in the progress of both writings (cf. cl. P. Patritii opus praestantissimum in Evangelia l. 1. c. 4. n. 46. seqq.). S. Irenaeus sets forth this scope of John more distinctly l. III. c. 11. The heretics, namely, the inventors of falsely so-called knowledge (I. Tim. VI. 20. cf. Coloss. II), from whom the sects of the Gnostics were propagated, having introduced a multitude of Aeons (so far as concerns the present), called one the Word, another the Christ, another the Savior, another the visible Jesus, whom some admitted to be a mere man, others not even a man truly born of the Virgin Mary. But all conspired in denying that Jesus himself is the Son of God, or is the Christ; but some in one way, others in another, fabled that the Aeon Christ or the Savior descended into Jesus at the baptism in the form of a dove, and at the time of the passion and death flew away again into the heavenly pleroma. « Announcing this faith, John, the disciple of the Lord, wishing through the announcement of the Gospel to take away the error which had been sown in men by Cerinthus and much earlier by those who are called Nicolaites, who are a shoot of that which is falsely named knowledge, in order to confound them, and to persuade them, that there is one God who made all things through his Word; and not as those say, one indeed the fabricator (δημιουργόν), another the Father of the Lord, and one indeed the son of the fabricator, another the Christ from above, whom they say also persevered impassible, descending into Jesus the son of the fabricator, and flew back again into his own pleroma... Therefore wishing to circumscribe all such things, the disciple of the Lord... began in the doctrine which is according to the Gospel: In the beginning was the Word... But according to them neither did the Word become flesh, nor the Christ, nor the Savior who was made of all (collected as it were by a contribution from all the Aeons). For they will neither that the Word and the Christ came into this world; but that the Savior, not incarnate and not having suffered, descended as a dove into that Jesus who had been made by the disposition, and when he had announced the unknown Father, ascended again into the pleroma... Others again say that Jesus indeed was born of Joseph and Mary, and that into him descended the Christ who is from above, existing without flesh and impassible. But according to no opinion of the heretics did the Word of God become flesh » Iren. l. c. n. 1-3. Although, however, it is not to be doubted that these monsters were variously arranged and cultivated in the about forty years which had flowed by from the writing of the Gospel and of the epistles of John up to Valentinus the Gnostic, that the principles and seeds of this falsely so-called knowledge had already been scattered in Asia minori in the very age of John the Apostle is both probable in itself, and is made certain both from the testimony of the most ancient Fathers and from the very form and manner of writing of the Apostle (cf. P. Patritium l. c. n. 11. sqq.).

Already from the obvious reading itself it is clear that this last chapter of the epistle too aims at this, v. 4-13. 20, that it be taught that that very Jesus who appeared visibly is both true man and the Christ and the true Son of God. « This is the victory which overcomes the world, our faith. Who is it that overcomes the world, but he who believes that Jesus is the Son of God? » There follows the bringing forward of the real testimony and of the formal testimony concerning Jesus, true man and true Christ, Son of God. « This is he who came through water and blood, Jesus Christ; not in water only, but in water and blood. And the Spirit is he who testifies, that Christ is the truth ». The passage is obscure, in that it admits several senses, among which for us, to whom not all the circumstances of refuting the error are known, it is difficult to determine the uniquely true sense; the Fathers and the interpreters too go off into diverse opinions.

If it could be certainly proved that the Apostle had before his eyes the condemnation of that heresy which imagined that Christ descended into Jesus, baptized in the form of a dove, and, the ministry of preaching being completed, in the passion and death of Jesus flew back again impassible into his heavenly pleroma; in this hypothesis, I say, the passage would most conveniently be understood in this sense: he, as one person who is Jesus, true man, and Christ, the Son of God, came and was manifested both in the baptism, by which he wished to begin his public life and the completion of our redemption, and in his passion and death; not only did Christ the Son of God come at the baptism upon Jesus the man, about to depart from him at the time of death; but one person, Jesus Christ, came and was manifested not in water (baptism) only, but in water and blood (in the effusion of blood and in death). Tertullianus (de Baptismo c. 16), Beda, Oecumenius, Anselmus Laudunensis (glossa interlinearis) indicate this sense in h. l. Nevertheless another interpretation seems more probable and simpler, according to which not only the effusion of blood, but also of water, on the cross is understood by the name of water, not, however, baptism. Thus thought Athanasius (contr. Apollin. l. I. n. 18), Augustinus (contr. Maximin. Arian. l. II. c. 22. n. 3), Eucherius Lugdun. (qq. in V. et N. T. Bibl. Max. PP. T. VI. p. 853), Strabo (in glossa ordinaria), Innocentius III. (de celebr. Missarum cap. In quadam l. III. tit. 41. c. 8) and others. Certainly this very conjunction of water and blood seems altogether to agree with the testimony Io. XIX. 34. 35, especially if one attends to the fact that with equal care in both places, both of the epistle and of the Gospel, this matter is inculcated, that from the pierced side of Christ there came out blood and water: « immediately there came out blood and water; and he who saw it bore testimony, and his testimony is true; and he knows that he says what is true, that you also may believe ».

Moreover there is doubt about the sense of the last clause: « the spirit (τὸ πνεῦμα) is he who testifies, that Christ is the truth ». In the first place one may doubt about the true reading. For the Greek text as now edited has: « ὅτι τὸ πνεῦμά ἐστιν ἡ ἀλήθεια, that the Spirit is the truth ». But both in the Greek and Latin codices and among the Fathers the reading is varied: some have Χριστός, others πνεῦμα. In the Latin Vulgate reading the object of the testification is that Christ is the truth: not merely an apparent man, as the Docetae said, nor a mere man into whom Christ descended; but the same is true man and true Son of God. « Although he suffered according to the man, says Anselmus Laudunensis (glossa interlin.), nevertheless the Spirit seen upon him, baptized in the form of a dove, or the spirit, i. e. every spiritual teacher, testifies this, that Christ is the truth, the true Son of God, not a phantasm ».

Moreover, concerning the name of spirit, whose testimony is brought forward in this verse 6°. together with the water and the blood, what properly must be understood, the opinions again are various. Since the testimony is joined from these three, from the water, the blood and the spirit, it seems to be required that both the water and the blood and the spirit be taken in the same signification in which v. 8. says « three, who give testimony on earth; the spirit and the water and the blood ». There indeed Athanasius, Augustinus, Eucherius Lugdunensis, Walafridus Strabo, Innocentius III, in the places indicated a little before, understand the spirit which Christ sent forth on the cross. « Indeed I do not wish you to be deceived in the epistle of John the Apostle, where he says: three are the witnesses, the spirit and the water and the blood, and the three are one... we know three things to have gone out of the body of the Lord, when he hung on the wood: first the spirit, whence it is written: and bowing his head he gave up the spirit; then, when his side was pierced with the lance, blood and water » Aug. cont. Maximin. l. II. c. 22. n. 3. Just as this interpretation of the water and blood poured out from the side of Christ, so also this one of the spirit sent forth on the cross can be recommended with Eucherius from this, that John in the Gospel (Io. XIX. 30. 34. 35) joins the poured-out water and blood with the sent-forth spirit as it were a real testimony of the humanity of Christ. For there, after it has been said: « bowing his head he gave up the spirit (παρέδωκεν τὸ πνεῦμα) », immediately in one series of discourse the history of the piercing of the side of Christ is connected: « and immediately there came out blood and water ».

But although these things are probable with respect to the spirit which is named in our epistle v. 8; the words nevertheless of verse 6, as they now are: « and the spirit is he who testifies, that Christ is the truth », with the greatest difficulty; in the other reading, however, « that the Spirit is the truth », in no way can they be understood of the soul of Christ, but altogether with the real testimony of the water and of the blood there seems to be joined the formal testimony of the Holy Spirit. In such a conjunction, indeed, with the water and the blood, the testifying Spirit can be understood as the Holy Spirit speaking through the Apostles and through testifying men¹. In this way John also in the Gospel joins with the real testimony of the blood and water flowing from the pierced side of Christ the testimony of the Spirit, namely his apostolic testimony, and inculcates the truth of this with special and unusual care: « immediately there came out blood and water; and he who saw it bore testimony, and his testimony is true, and he knows that he says what is true, that you also may believe ». Thus, therefore, by the name of spirit v. 6°. and perhaps also v. 8°. there can be understood the gift and effect of the Holy Spirit in the Apostles or generally in the Church, which elsewhere also is metonymically called Spirit. « The spirit, i. e. every spiritual teacher, testifies, that Christ is the truth » Glossa interlin.². Although, therefore, it might be conceded that the same Holy Spirit is named in all three verses 6. 7. 8; still he would not be understood to testify in the same way in v. 6. and 8. as in v. 7, and thus there would be distinguished the Holy Spirit testifying in heaven personally and per se immediately, and testifying on earth through his gifts in the Apostles and in the Church.

From these things it now appears that the connection of verses 7. and 8. with the preceding 5°. and 6°. is most close. For to that point, that Jesus is the Son of God and that he came in water and blood, and the Spirit testifies that Christ is the truth; there follows in v. 7°. and 8°. a further explanation of the testification. The object of the testification is indicated as twofold, that Jesus is the Christ, the Son of God, and that he is true man. For each distinctly the testimony of three is brought forward; just as also Christ the Lord, speaking to the Jews, brought forward two testifying

the Father and himself, appealing to that: in the mouth of two or three witnesses every word shall stand (Deut. XIX. 15), and afterwards, in the further instruction of the disciples, added the Holy Spirit testifying Io. V. 31-39; VIII. 14-18; XV. 26. What, therefore, the Apostle had said a little more obscurely about the testifying ones v. 6: « this is he who came through water and blood, Jesus Christ... and the Spirit is he who testifies, that Christ (or the Spirit) is the truth »; this he distributes in v. 7°. and 8°. into the testimony in heaven for the divinity, and the testimony on earth for the humanity³, noting on both sides the ternary number. « John the Apostle speaks in his epistle saying: three are they who give testimony in heaven, the Father, the Word, and the Holy Spirit, and these three are one; intending through this to show that Christ is true God. And three are they who give testimony on earth, the spirit, the water, and the blood; intending through this to show that Christ is true man » Innoc. III; Walafrid. Strabo ll. cc.

II. What we have said up to now pertains only to determining the context and sense of v. 6°. and 8°. Now at last we must come to the demonstration from v. 7°., about which we are at present concerned. The distinction of persons, which in the form of baptism is demonstrated by the signification of the names and by the connumeration of the three, is here expressly enunciated: the Father, the Word, and the Holy Spirit are three testifying ones. Likewise the unity of the Father and of the Son and of the Holy Spirit according to the Godhead and absolute perfection, which we showed to be exhibited in the form of baptism, is here enunciated by the expressed name of unity:

Baptizing them in the name — And these three are one: of the Father and of the Son and of the Spirit — three are they who give testimony in heaven, the Father, the Word, and the Holy Spirit. Holy.

1°. The thing to be testified is enunciated in v. 5. 6, that Jesus is the Christ, the Son of God. The testimony is twofold; the first formal. For immediately there is subjoined in v. 9: « God (namely the Father, for the name God is determined by the added phrase concerning his Son, so that it stands for the hypostasis) has testified concerning his Son ». This testimony of the Father concerning his Son, and the testimony of the Son himself and of the Holy Spirit, has been given in many ways, and has been frequently appealed to by the Son, so that now two, now all three persons are named together in testifying. « And he saw the Spirit of God descending as a dove and coming upon him, and behold a voice from heaven saying: this is my beloved Son (ὁ υἱός μου ὁ ἀγαπητός) Mt. III. 16. 17; « when the Paraclete will come, whom I shall send to you from the Father, the Spirit of truth who proceeds from the Father, he will bear testimony of me » Io. XV. 26. cf. ib. XVI. 14. 15; « I am he who bears testimony of myself, and he who sent me, the Father, bears testimony of me » ib. VIII. 18. cf. ib. X. 25 seq.

In the other way, the real testimony concerning this truth, that « Jesus is the Son of God », is contained in this very fact, that the Father, the Word, and the Holy Spirit are three one. This argument, or real testimony, moreover, holds itself in two ways. a) Through the unity of the three the formal testimony itself is demonstrated to be divine, not only inasmuch as it is from the Father, but also inasmuch as it is from the Son and from the Holy Spirit, because the Son and the Spirit are one with the Father: three are they who give testimony, and these three are one; whence immediately concerning this testimony of the three there is inferred: « the testimony of God is greater ». b) This unity of the three exhibits by itself, and thus not only in words but in reality testifies, the true and proper divine filiation of Jesus Christ. For the Word made flesh is itself Jesus Christ, as John demonstrated at the beginning of the Gospel to which the epistle adheres (the Word was made flesh, and we saw his glory, glory as of the only-begotten from the Father); but the Word is the proper Son of God through the unity of nature, which he has communicated from the Father, and which the Word himself, with the Father, communicates to the Holy Spirit. Therefore the unity of the three demonstrates and really testifies through itself, « that Jesus is the Son of God »; namely the proper Son and through nature one with the Father; « Jesus is the Son of God (the truth to be testified): for three are they who give testimony in heaven, the Father, the Word, and the Holy Spirit (the testifying persons); and these three are one (the formal reason through which they testify) ». Wherefore, just as the spirit, the water, and the blood on earth are by themselves a real testimony for the true humanity of Jesus Christ; so the three in heaven by themselves, inasmuch as they are one, or through their unity, are said to be a real testimony for the true divine filiation, i. e. for the divine nature of Jesus Christ. Therefore, when John enunciated as the formal reason of this real testification that « these three are one », he could not have understood any other unity of the three than that of nature. The doctrine, therefore, of John is reduced to this enthymeme. Three persons in heaven, the Father, the Word (the incarnation not yet considered), and the Holy Spirit are one in nature: therefore the incarnate Word, Jesus Christ, is the true Son of God through a nature one with the Father and the Holy Spirit.

2°. Although the words of the Apostle, who by excellence has the name of theologian, are in themselves most clear; nevertheless the Socinians and — what is certainly wonderful — also some Catholics (Placidus Stürmer, Dobmayr etc.) found a difficulty against the force of the proof from this text. The clause « three are one » v. 8, they say, indicates not a unity of nature but only a moral unity, namely the agreement of the testimony; therefore neither from v. 7 can any other unity be demonstrated. In the first place in the clause: « these three are one », between verse 7. and 8. neither is the verbal parallelism undoubted, certainly there is no real parallelism. For in the Greek editions (except the Complutensian) v. 7. is: ἕν εἰσι, they are one; v. 8. however: εἰς τὸ ἕν εἰσι, they are in one. In the Complutensian v. 7. is read: εἰς τὸ ἕν εἰσι; v. 8. this clause is altogether lacking. So also in many Latin codd. only concerning the witnesses in heaven is read: « and these three are one »; concerning the witnesses on earth, however, it is omitted. Of which variety, besides the codices themselves which exist, we have as witness the Council Later. IV. (Hard. VII. p. 18). So also s. Thomas (commentar. in II. decretal. de errore abb. Ioachim. ed. de Rubeis T. VIII. p. 94) says on v. 8.: « in certain books there is attached: and these three are one; but this is not had in the true exemplars, but in certain books it is said to have been added by the Arian heretics to overturn the sound understanding of the authority premised (v. 7) concerning the essential unity of the three persons ». Elsewhere v. 8. is read: « and these three are in us », as with the author of the book adversus Varimadum (Bibl. Max. T. V. p. 729); the author of the book de bapt. haeretic. of the III. century reads in Latin, as it is in the Greek: « and these three are in one »; elsewhere it is added by way of explanation: « these three are one in Christ Jesus », as in the Speculum of Augustinus (ed. Mai); cf. Cassiodorus or the interpreter of the commentary of Clemens Alex. in r. Io. (Bibl. Max. T. III. p. 234). Cassiodorus himself in the Complexiones ed. Maffei p. 145. omits the clause of v. 8., and for v. 7. gives the interpretation: « and these three are one God ». These things show that a great difference has always been recognized, at least in sense, concerning the words « are one » between v. 7. and v. 8. Moreover the reading of v. 8. εἰς τὸ ἕν, εἰσι, seems sufficiently certain both from the Greek Fathers and from the codices. In v. 7., however, according to the Fathers and the Latin codices, by which this text has been preserved for us, and from the comparison with Io. X. 30. (ἕν ἐσμεν), the reading ἕν εἰσι is to be judged true, as it is cited by the Council Later. IV. also in the Greek version (Hard. l. c.), and it stands in the Greek codex of Dublin Coll. SS. Trinitatis⁴ (which seems to be the same as the British codex of Erasmus), and also in the editions among the schismatic Greeks (see Professionem fidei orthodoxae probatam a quatuor Patriarchis aliisque Episcopis schismaticis ed. Lipsiae P. I. q. 9. p. 25).

This being posited, it is manifest in the words themselves that one unity of the Father, of the Word and of the Holy Spirit is enunciated, and another of the spirit, of the water and of the blood. The Father, the Word, the Holy Spirit are said to be three one simply; the spirit, the water and the blood are said to be in one, namely to pertain to one and the same truth to be demonstrated and testified, or to be one in testimony.

Let us indeed concede the verbal parallelism, such as certainly exists in our Vulgate, so that in both places it is said: «and these three are one»; yet the real parallelism must surely be denied. The subject in each verse is utterly different: in the former, the Father, the Word, and the Holy Spirit; in the other, the spirit, the water, and the blood. But in proportion to the diversity of the subjects the signification of the predicate is also modified, especially if the subject in one proposition is God and in the other something created; for who would say that the same thing is signified, e. g., by the predicate of wisdom in the two propositions: God is wise, — man is wise? Now the signification of the subject in verse 7° is evident at least to this extent, that the Father is true God, that the Word and the Holy Spirit are not divine attributes, but are really distinct both from the Father and from one another; for they are said to be «these three». They are therefore subsistent in themselves; and since from the very name Word and Holy Spirit (not to appeal now to the whole doctrine of the Scriptures) they are shown to be of intellectual nature, they are three persons. Three persons, therefore, of which one is certainly God, no one — not even a heretic — denying it, are predicated to be one; and this not by sub-numerating but by evidently co-numerating the three persons: these three are one (see Coroll. I. to th. III). But concerning such co-numeration of persons the principle of St. Augustine is most certain. Augustine affirms, after the manner of a hermeneutic and dogmatic principle, that in the Scriptures things whose substance is diverse are never predicated to be one simply⁵. St. Thomas restricts it to this sense: that God and a creature are never said to be one simply (S. Th. in Io. X. 30. lect. V.). To Bellarmine (de Christo l. I. c. 6) the principle seemed, even in this sense, less firm; for just as it is said: «he who adheres to the Lord is one spirit» 1. Cor. VI. 17; so, he says, it could also be said: he is one with God; «for one spirit is one thing, and one thing and one and the same are the same». But first of all (be it said with deference to so great a man) spirit there is not a substance, but is the supernatural gift of faith, hope, and charity derived from Christ, the Christian intellect, the Christian will, which Paul said elsewhere: «we have the mind of Christ», and again: «have this mind in you, which was also in Christ Jesus» (1. Cor. II. 16; Phil. II. 5). In this sense, however, «one spirit» with Christ certainly does not mean the same as «one thing with Christ, and one simply». But if the Spirit were understood as a cause, then surely the Spirit of the Lord dwelling in the just, and the Lord — or the Spirit of the Son, and the Son — are one simply. Thus Pseudo-Ambrosius explained it in his commentary on this passage: in the just, he says, «the Spirit of God is common with God and men». With this interpretation can be compared all the places in which there is speech of the communication and indwelling of the Holy Spirit, as that: «whoever are led by the Spirit of God, they are the sons of God» Rom. VIII. 14. Moreover, between "one" said simply and the determining locutions, in what several things are one, the great difference is this, that "one" said without addition, having the simplest notion, does not admit several significations; but if it has some addition, this can be of such a kind that it may be taken in a signification by which the species of unity is determined, not substantial but accidental, of which kind is also that name 1. Cor. VI. 17. one spirit. Read about these things St. Augustine against Maximin. l. II. c. 20. n. I.

Furthermore, although by a very improper locution a man could perhaps be said to be one with God, Augustine's principle would still remain most true where there is question of the biblical usage of speech and of the co-numeration of persons, of which one is God: namely, that in the Scriptures no person besides the Son of God and the Spirit of God is ever co-numerated with God the Father or with God in such a way that God and that person are said to be one. Indeed, even prescinding from the usage of speech of the Scriptures, it is universally evident that persons, of whom one is certainly true God, cannot be co-numerated in the same line of dignity without the predicate «they are one» being taken ontologically of the unity of being, or of the divine Esse; just as it is said in this place: there are three who give testimony in heaven, the Father, the Word, and the Holy Spirit.

What we say about the biblical usage of speech is established by induction and by consideration of the places of Scripture Io. XVII. 11. 20. 21. (cf. Aug. contr. Maximin. l. c.); I. Cor. VI. 17; I. Io. V. 8, which have been accustomed to be objected chiefly by the Arians and by the Unitarians in order to obscure this testimony of I. Io. V. 7.

The reason of the principle, in which sense we said it is universally evident, easily appears, because namely by such co-numeration itself the equality of the persons in some line of perfection or dignity is declared; but equality with God (for one of the co-numerated persons is supposed to be God) cannot be enunciated by the predicate, they are one, without this being taken in its proper sense, in which it signifies one being⁶. For no unity of equality with God can be conceived which is not really a unity of essence; but according to our distinctions of reason, the unity of essence is the first and fundamental one, which is supposed by every unity distinct by reason, and with which every other unity, e. g. of absolute attributes, of actions and relations ad extra, is identified. Whence he who to the sentence: «the Father, the Word, the Holy Spirit, three are one», adds the explanation: they are one in power, in will, in authority of testimony, either, intending to exclude the unity of essence, speaks absurdly of divine things, or really says the same thing that is the unity of essence, while he considers the unity in the attributes and actions ad extra, which are distinguished from the essence not otherwise than by our manner of thinking and by reason. Just as therefore in the proposition: «the Father, the Word and the Holy Spirit give testimony in heaven», by the very names and by the very co-numeration in the plural number the distinction is already taught, which afterwards is explicitly enunciated by the particle «they are three»; so by the very co-numeration of the Word and of the Holy Spirit with God the Father in the same order of dignity the unity of the Godhead of the three distinct ones is already contained, and this unity is explicitly and expressly proclaimed by the declaration: «these three are one».

On the contrary, however, the subject of verse 8°, «the spirit, the water and the blood», is of an entirely different order. Water and blood certainly are not persons, much less divine persons, but are created things. Therefore, however the second subject, the spirit, is understood, the predicate «they are one» cannot have the same signification as in verse 7° in the co-numeration of the Father, the Word, and the Holy Spirit. If moreover the Greek text is consulted: «εἰς τὸ ἕν εἰσι, they are unto one», it appears that the unity is enunciated not so much among those three as toward the thing to be testified; whence even in the Latin text those three must be understood as one in testimony. But this unity of testimony, in divine things indeed, supposes the unity — and that a numerical unity — of nature; in created things, however, it requires neither numerical nor specific unity.

To the difficulty therefore proposed, in which it was said: by that «three are one» v. 8 a moral unity in testifying is indicated; therefore no other is indicated in v. 7 by the same words; it is answered a) by denying the consequence. For the subjects are utterly different in each verse, and therefore the signification of the predicate «they are one» is also different. b) Inasmuch as the three in heaven, the Father, the Word, and the Holy Spirit, exhibit a real testimony and demonstration that the incarnate Word is the true Son of God, they exhibit this testimony not otherwise than by the unity of nature, because namely the Word is God and of one nature with the Father and the Holy Spirit. Therefore by the words «three are one», by which is contained why and how the three persons exhibit testimony for the true divine filiation of Jesus Christ, nothing else can be signified than the unity of the three according to the divine nature. c) Inasmuch as the three persons in heaven give formal testimony for the divine filiation of Jesus Christ, the authority of this testimony is one, because the nature of the three is one. «My Father works until now, and I work... the Son cannot do anything of himself, except what he has seen the Father doing; for whatever he has done, these the Son also does in like manner» Io. V. 17-23. «The words that I speak to you, I do not speak of myself; but the Father abiding in me, he does the works» ibid. XIV. 10. «But when he, the Spirit of truth, comes, he will teach you all truth, for he will not speak of himself, but whatever he will hear he will speak... He will glorify me, because he will receive of mine and will announce it to you. All things whatsoever the Father has are mine. Therefore I said that he will receive of mine and will announce it to you» ib. XVI. 13-15. What is said therefore: «three are one», contains the reason why, just as every operation ad extra is one of the three, so the testimony is one by which the three testify, the Father, the Word of the Father, and the Spirit of the Father and of the Son; the reason namely is the one Esse, or the unity of essence⁷.

3°. The genuine sense vindicated thus far is confirmed by comparison with what follows.

For with verse 7° v. 9 is closely connected: «If we receive the testimony of men, the testimony of God is greater (cf. Io. V. 32. seq.; VIII. 17. 18); because this is the testimony of God, which is greater⁸, because he has testified of his Son. He who believes in the Son of God has the testimony of God in himself». For he had called the testimony of three distinct ones, the Father, the Word, and the Holy Spirit, about Jesus the true Son of God; but at the same time he had declared: «these three are one». Now that testimony of the three he calls the testimony of the one God; and so that: «these three are one», is equivalent to the other proposition: «these three are one God». Whence Cassiodorus, who in his Complexiones, together with many codices and Fathers, places verse 7 after our verse 8°, and thus even by the material collocation of the words preserves the connection, rightly circumscribes the clause «are one» by this other one: «and these three are one God». The Apostle himself therefore declares the reason by which the three are one: that the three distinct ones, the Father, the Word, and the Holy Spirit, are one God, and consequently are one by the unity of the divine nature, which admits no multiplication.

We have declared the testimony of God v. 9 as the testimony of the one God absolutely considered; against this explanation a difficulty could arise for someone from those things which John subjoins: «the testimony of God, because he has testified of his Son», where the testimony of God the Father is evidently understood. But the name God is of itself not a relative name (for it does not express a relation to another) but an absolute one, signifying the divine nature after the manner of a concrete thing and therefore after the manner of a hypostasis, but without the determination of this or that distinct person. Since therefore the three are one God, both singly and all together, the name God without an added determination does not supposit for one person distinct from the others, but signifies the Godhead subsisting in the three persons. Yet because the individual persons are God, by an added personal property the name God is determined, so that it supposits for one person whose property is expressed (see above p. 31. seq.). Thus in the proposition: God begets God, the subject is determined to supposit for the person of the Father alone by the added property of active generation, and the predicate supposits for the Son alone, because of the included property of passive generation (τὸ γεννητόν). Hence it is clear that, without any confusion or obscurity, in the same context the name of God can be taken now absolutely for God, who is one and triune, now with a determined supposition for one person; for neither is the signification of the name changed by this variety, which always remains the same, namely of the divine nature after the manner of subsisting: but there is only a transition from indeterminate supposition to a distinct supposition, which is clearly expressed by the added personal notion. Thus also in created things no one would say that this speech is obscure: man needs grace for the confession of faith; therefore the man confessing: you are the Christ, the Son of the living God, was illuminated and strengthened by grace; although the name man passes from confused supposition to a determined supposition for Peter. Which things being posited, no one will deny that in the former clause of v. 9: «the testimony of God is greater», the name God is taken absolutely, namely the testimony of God the Father, the Word, and the Holy Spirit, who are three and are one; but in the other clause: «because (God) has testified of his Son», the subject God supposits for the person of the Father alone.

From these things it is clear, a) that the testimony, or the same act of testifying (ἡ μαρτυρία), is absolutely one and the same, whether it is said of the Father, or of the Son, or of the Holy Spirit, or of the Father, the Son, and the Holy Spirit together; and consequently that the act ad extra is one and really common to the three persons, because they do not act inasmuch as they are persons distinct by relation to one another, but inasmuch as they are one God. b) Since the act or operation in God is the very divine nature itself with the connotation of a term ad extra; by this very fact, through the unity of the testimony, which is absolutely one and the same, whether it is said of one or of another or of the three persons, the unity of nature in the three persons is most manifestly expressed as a consequence. c) You will notice in passing again what we said in the preceding thesis: that the context can scarcely, or not even scarcely, hold together if verse 7, about the testimony of the three in heaven, is lacking. For when v. 9 says: the testimony of God (about the divine filiation of Jesus Christ) is greater, it is supposed that the narration of the existence of this testimony of God has preceded; but this narration exists nowhere except in verse 7°.

As a finishing touch it seems opportune to set before the eyes the parallelism of this place now explained, I. Io. V. 5-13, with the texts Io. I. 1-18; X. 25-38, declared in thesis III.

Io. I.	1. Io. V.	Io. X.
In the beginning was the Word... And the Word was made flesh, and we saw his glory, glory as of the Only-begotten from the Father v. 1. 14.	Who is he who overcomes the world, but he who believes that Jesus is the Son of God v. 5.	My Father, what he has given me, is greater than all things..... You make yourself God..... I said, I am the Son of God...... That you may believe, that the Father is in me and I in the Father v. 29. 33. 36. 38.
In him was life, and the life was the light of men v. 4.	And this is the testimony, that God has given us eternal life. And this life is in his Son v. 11.	I give them eternal life v. 28.

Io. 1.11-12	1 Io. 5.12-13	Io. 10.26-28
He came to his own, and his own did not receive him; but as many as received him, he gave them power to become sons of God, to those who believe in his name.	He who has the Son has life; he who does not have the Son does not have life. These things I write to you, that you may know that you have eternal life, you who believe in the name of the Son of God.	You do not believe, because you are not of my sheep. My sheep hear my voice, and I know them, and they follow me, and I give them eternal life, and they will not perish forever.

No one has ever seen God: the only-begotten Son, who is in the bosom of the Father, he has declared him... I saw the Spirit descending as a dove from heaven and remaining upon him... He who sent me to baptize in water, he said to me: he upon whom you see the Spirit descending and remaining upon him, this is he who baptizes in the Holy Spirit v. 18. 32. 33.

Io. 1.1	1 Io. 5.7	Io. 10.25, 37-38
(In the beginning was the Word), and the Word was with God, and the Word was God v. 1.	Because there are three who give testimony in heaven, the Father, the Word, and the Holy Spirit, and these three are one v. 7.	The works that I do in the name of my Father, these bear testimony of me... If I do not do the works of my Father, do not believe me. But if I do them, and if you do not want to believe me, believe the works, that you may know and believe, that the Father is in me, and I in the Father v. 25. 37. 38.

And no one will snatch them out of my hand, and no one can snatch out of my Father's hand: I and the Father are one v. 28-30.