To the integrity of this book, there is only one exception. The integrity of a book is established when it comes to us in the shape it was originally delivered, it has not lost anything out of it, and nothing has been added to it. Now, as to the integrity of this book, there is one exception. In the King James version, John 5:7, 8, reads: “For there are three that bear witness in heaven, the Father, the Word and the Holy Ghost, and these three are one.” Now look at the 8th verse, two words of the second line, “in earth”—“there are three that bear witness in earth.” Let us take out of the King James version all the 7th verse and the words, “in earth,” of the 8th verse. They are unquestionably an interpolation. They do not appear in any of the ancient manuscripts, and our standard version leaves them out. So our standard version reads: “For there are three who bear witness”—it does not say anything about any three in earth or in heaven—“the Spirit, and the Water, and the Blood, and the three agree in one.”
With the exception of that 7th verse and the words “in earth” of the 8th verse of the common version, which certainly are an interpolation by a much later writer (probably a copyist put them in to fill out his ideas)—they do not show in any reputable authentic text—the book is strictly authentic.
Carroll, B. H. (1915). The Pastoral Epistles of Paul and I and II Peter, Jude, and I, II and III John (J. B. Cranfill, Ed.; pp. 326–327). Fleming H. Revell Company.