From Gill:
1 John 5:7
For there are three that bear record in heaven,.... That is, that Jesus is the Son of God. The genuineness of this text has been called in question by some, because it is wanting in the Syriac version, as it also is in the Arabic and Ethiopic versions; and because the old Latin interpreter has it not; and it is not to be found in many Greek manuscripts; nor cited by many of the ancient fathers, even by such who wrote against the Arians, when it might have been of great service to them: to all which it may be replied, that as to the Syriac version, which is the most ancient, and of the greatest consequence, it is but a version, and a defective one. The history of the adulterous woman in the eighth of John, the second epistle of Peter, the second and third epistles of John, the epistle of Jude, and the book of the Revelations, were formerly wanting in it, till restored from Bishop Usher's copy by De Dieu and Dr. Pocock, and who also, from an eastern copy, has supplied this version with this text. As to the old Latin interpreter, it is certain it is to be seen in many Latin manuscripts of an early date, and stands in the Vulgate Latin edition of the London Polyglot Bible: and the Latin translation, which bears the name of Jerom, has it, and who, in an epistle of his to Eustochium, prefixed to his translation of these canonical epistles, complains of the omission of it by unfaithful interpreters. And as to its being wanting in some Greek manuscripts, as the Alexandrian, and others, it need only be said, that it is to be found in many others; it is in an old British copy, and in the Complutensian edition, the compilers of which made use of various copies; and out of sixteen ancient copies of Robert Stephens's, nine of them had it: and as to its not being cited by some of the ancient fathers, this can be no sufficient proof of the spuriousness of it, since it might be in the original copy, though not in the copies used by them, through the carelessness or unfaithfulness of transcribers; or it might be in their copies, and yet not cited by them, they having Scriptures enough without it, to defend the doctrine of the Trinity, and the divinity of Christ: and yet, after all, certain it is, that it is cited by many of them; by Fulgentius (z), in the beginning of the "sixth" century, against the Arians, without any scruple or hesitation; and Jerom, as before observed, has it in his translation made in the latter end of the "fourth" century; and it is cited by Athanasius (a) about the year 350; and before him by Cyprian (b), in the middle, of the "third" century, about the year 250; and is referred to by Tertullian (c) about, the year 200; and which was within a "hundred" years, or little more, of the writing of the epistle; which may be enough to satisfy anyone of the genuineness of this passage; and besides, there never was any dispute about it till Erasmus left it out in the, first edition of his translation of the New Testament; and yet he himself, upon the credit of the old British copy before mentioned, put it into another edition of his translation. The heavenly witnesses of Christ's sonship are,
From Clarke:
1 John 5:7
There are three that bear record - The Father, who bears testimony to his Son; the Word or Λογος, Logos, who bears testimony to the Father; and the Holy Ghost, which bears testimony to the Father and the Son. And these three are one in essence, and agree in the one testimony, that Jesus came to die for, and give life to, the world.
But it is likely this verse is not genuine. It is wanting in every MS. of this epistle written before the invention of printing, one excepted, the Codex Montfortii, in Trinity College, Dublin: the others which omit this verse amount to one hundred and twelve.
It is wanting in both the Syriac, all the Arabic, Ethiopic, the Coptic, Sahidic, Armenian, Slavonian, etc., in a word, in all the ancient versions but the Vulgate; and even of this version many of the most ancient and correct MSS. have it not. It is wanting also in all the ancient Greek fathers; and in most even of the Latin.
The words, as they exist in all the Greek MSS. with the exception of the Codex Montfortii, are the following: -
“1Jo_5:6. 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 beareth witness because the Spirit is truth.
1Jo_5:7. For there are three that bear witness, the Spirit, the water, and the blood; and these three agree in one.
1Jo_5:9. If we receive the witness of man, the witness of God is greater, etc.”
Scofield:
1 John 5:7
It is generally agreed that (1Jo_5:7) has no real authority, and has been inserted.