The extent and character of the continuity and the differences between prophecy and apocalyptic are highly debatable. But the distinction means that the relationship between Revelation and the Jewish apocalypses has also been debated. Often the issue has been posed in a misleading way, as though John himself would have made the kinds of distinction modern scholars have made between prophecy and apocalyptic. This is very unlikely. The book of Daniel, which was one of John's major Old Testament sources, he would certainly have regarded as a prophetic book. If he knew some of the post-biblical apocalypses, as he most probably did, he will have seen them as a form of prophecy. The forms and traditions which Revelation shares with other works we call apocalypses John will have used as vehicles of prophecy, in continuity with Old Testament prophecy.