Many scholars in a former generation thought that Zoroastrian ideas had influenced the concept and structure of the millennium in Rev 20. More recently, however, nearly all scholars who deal with Revelation think rather that Ps 90.4 was responsible for the formulation in Rev 20. A careful review of both Jewish and Zoroastrian texts that bear on the issue, however, shows that, while absolute proof may be lacking, we should still give very serious consideration to the likelihood of a Zoroastrian background.