In revelations 22:18-19 what does it mean?

it means if you alter the Book of Revelations in any way, God will pwn you.

It means if you add things to what is already written in the book of Revelation, God will cause plagues and bad things to come upon you. If you take anything away, you're not going to get into heaven and your name will out of the book of life.

It means you are not allowed to change The Word like the priests have done already.

All of the modern translations of the Bible are WRONG. The only previous translation that is any good is the Original king James' Authorised Version Bible and even it has been incorrectly translated in places and the Books in it are not in their correct chronological order (Please read the following King of kings' Bible "contents page" for the correct order of Books). However, I have now completed the "King of kings Authorised Version of the Holy Bible" (the text of which is older than the kJAV; has the Thees and Thous and is more accurately interpreted and more informative than the kJAV but in PERFECT harmony with it, using mostly the same text but having capital letters when referring to God - He; Him; His; Thine; Thou; Who etc. to make it easier to understand; with notes included in the text to make things clear. It also contains that which was wrongfully removed.) under God's/Allah's supervision

It is also necessary for king James' Bible students to study this ORIGINAL version of the Koran, in order to understand some Biblical things more clearly and to be able to quote the True Koran to our moslem brothers and bring the world together in peace, under The Covenant, before it is TOO late.

I have written many works on the king James' Bible and Biblical prophecy fulfillment (including The Invasion of Kuwait in Prophecy and "The Four Horsemen of the Apocalypse") and much more.

http://jahtruth.net/kofkad.htm

If you read up a few verses, you'll see that Jesus admits that he and Lucifer are one in the same:

"I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star." - Rev 22:16

So, that means he'll set you on fire forever if you screw with his demon book.

be careful when you copy The Revelation of St John the Divine.

The Revelation, as given to John of Patmos, is as it is to be.... I do not personally believe that injunction refers to what is now called "The Bible".....though The Word and Will of God, for man-kind, was, and still is, complete in Christ.

It means that Joe Hovah reserves the right to kick your @$$ out of heaven...

also means, JWS and Mormons are doing that very thing and are Cults!! period.