The official name of the last book of the Bible is “The Revelation of Jesus Christ“. Many commentators understand this to mean that it is a revelation about Jesus Christ, because of the wonderful revelation of Jesus which we find in the book. However, the book is clear; the purpose is “to show to His bond-servants, the things which must soon take place” (1:1).
This is therefore “The Revelation of Jesus Christ“ in the sense that it has been provided by Him. Of all the books in the Bible, this is the book that came to us with the least interference by man. John just wrote down what he heard and saw. He did not try to interpret it.
We therefore have books by Paul and John and Luke and many other men. There is only one book directly by Jesus Christ.