"1 John 5:7 ('the Father, the Word, and the Holy Spirit, and these three are one') belongs in the Bible."
Late Latin addition. Not in any Greek manuscript before the 14th century.
Evidence card
The rating is tied to the stated evidence, the stated caveat, and the named source trail below.
What's actually true
It appears in the Latin Vulgate (in some later manuscripts) and entered Erasmus's third edition (1522), then the Textus Receptus, then the KJV.
What gets left out
Absent from every pre-14th-century Greek manuscript. Not cited by any Greek Father in the Trinitarian controversies of the 4th century — they would certainly have used it if they had it. Erasmus only added it under pressure. Modern translations (including the NKJV, in a footnote) acknowledge this. The Trinity is still defensible from the rest of the New Testament — but not from this verse.
Source trail
Named scholarship, catalogues, or projects used for this claim rating.