1 John 5:7
"For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one."
This passage is often referred to as proof that there are three persons in the Trinity, and that the three are one.
The Jerusalem Bible is a Roman Catholic version translated into English from the Hebrew, Aramaic and Greek, and not from the Latin Vulgate (the Vulgate being the official "Bible" of the Roman Catholic Church). It bears the imprimatur of Cardinal Heenan. The "three heavenly witnesses" of 1 John 5:7 (A.V.) disappears completely in The Jerusalem Bible, replaced with a footnote giving the textual evidence against it and saying that the words were "probably a gloss which has crept into the text."
Erasmus in the first two editions of his Greek translation of the New Testament omitted the corrupt passage relating to the "three witnesses" (1 John 5:7). He did this for sound critical reasons. But the Vulgate, the Bible of the Roman Catholic Church, included the passage, and immediately the cry arose that Erasmus was tampering with the scriptures. Thinking he was safe, he rather rashly said he would insert the passage in his next (third) edition if a single Greek manuscript could be found that contained it. Surprisingly one was found, and he kept his word and inserted the disputed passage, much against his will and judgment, in the third edition of the Testament. But it turned out that the "discovered" manuscript (the Montfort manuscript), now in Trinity College Library, Dublin, which was the document submitted to Erasmus, is but a 15th century production of no critical value, and the disputed words are taken from some corrupt Latin manuscript. Erasmus added the passage to his 1522 edition, "but he indicates in a lengthy footnote his suspicions that the manuscript had been prepared expressly in order to confute him." Indeed the manuscript was written after Erasmus's request by a Franciscan from Oxford.2 It was this third edition which became a chief source for the King James Version, thereby fixing the passage firmly in the English-language scriptures for centuries.Out of the thousands of manuscripts currently extant which contain the New Testament in Greek, the disputed passage only appears in eight. The oldest known occurrence appears to be a later addition to a 10th century manuscript now in the Bodleian Library.
No Syriac manuscripts includes the passage. Coptic manuscripts and those from Ethiopian churches also do not include it.The two major translations of the 20th century, the RSV and NIV, do not have those spurious phrases in them.
The Cambridge Paragraph Bible, an edition of the King James Version published in 1873, and edited by noted textual scholar F. H. A. Scrivener, one of the translators of the English Revised Version, set the 1 John 5:7-8 passage in italics to reflect its disputed authenticity, though not all later editions retain this formatting.