Name of the last canonical book of the New Testament and which describes an apocalyptic prophecy. It is considered to be one of the most controversial and difficult books of the Bible, so much so that it was the only book of the New Testament on which John Calvin did not write a commentary. Since the author of Revelation identifies himself as John, many in the past have thought that the Apostle John was its author. Nowadays, many question this authorship due to the many inconsistencies in grammar and style between the Gospel of John and the book of Revelation. Textual evidence has made it clear that the author of the latter was far less familiar with the Greek language than the Gospel's author. Since the author was on the island of Patmos when he received his visions, he is generally referred to as John of Patmos.