{I testify} (Eg(9320)martur(935c)). Commentators disagree keenly
about the words in verses  18,19 . Charles rejects them as an
interpolation and out of harmony with the rest of the book.
Beckwith takes them to be John's own warning, drawn from  De 4:2 
"to every man that heareth" (panti t(9369) akouonti, dative of the
articular present active participle of akou(935c), which compare
 1:3 ). Swete properly holds these verses to be from Jesus
himself, still bearing solemn witness to this book, with warning
against wilful perversion of its teachings. {If any man shall
add} (ean tis epith(8869)). Condition of the third class with ean
and the second aorist active subjunctive of epitith(886d)i, with
epi added with auta, as also in the conclusion epith(8873)ei ep'
auton (future active). This warning is directed against
perversions of this book, not about the New Testament or the
Bible as a whole, though it may be true there also. Surely no
warning was more needed when we consider the treatment accorded
the Apocalypse, so that Dr. Robert South said that the Apocalypse
either found one crazy or left him so.