The Canon is Closed
I testify to everyone who hears the words of the prophecy of this book: if anyone adds to them, God will add to him the plagues which are written in this book; and if anyone takes away from the words of the book of this prophecy, God will take away his part from the tree of life and from the holy city, which are written in this book. – Revelation 22:18-19 (NASB)
The book of Revelation is the revelation of Jesus Christ. The passage quoted above remind us we are dealing with God’s Word and not man’s. Given the threats found within, it is evident that the Lord Jesus would have us take both the book and His threats seriously.
These words are often applied to the entirety of the 66 books of Scripture, and well they should. Nothing is to be added nor subtracted.
True, the above passage applies directly to what John has written by inspiration and revelation to the book of Revelation specifically, nevertheless, the warning given here must be applied to the whole of the Bible and for the following reasons:
First, God has inspired and caused Scripture to be written. 2 Timothy 3:16 tells us that all of Scripture, from Genesis to Revelation, “is inspired by God” and all that has been written in these holy Scriptures were written for the purpose of teaching us (Romans 15:4). Surely, all Christians will agree that this is so.
Secondly, God, in His wisdom and providential watch care over His Word to mankind, has so arranged His communication to us that this specific book, the Revelation, was at the end. Because of this, one may easily see that the warnings concerning the revelation of Jesus Christ, in light of the purpose of Scripture, and which was given through the Apostle John, are applied to the entirety of Scripture.
God has spoken through His appointed authors, for the purpose of instructing us, so naturally, nothing is to be added nor subtracted from the Bible. For anyone to add or subtract to it, or claim modern day, extra-biblical revelation, is to play God and to reject out of hand His ominous warnings.