Author and Date
Iranaeus said the Revelation was written in the mid 90s in the reign of the Emperor Domitian , and this is now widely accepted [20 p.5]. Ancient tradition [20 p.7] and some commentators identify the author with John the beloved disciple and author of John's Gospel ; others disagree, because he does not describe himself as an apostle, the Greek is worse than that of the Gospel, and perhaps the book was written too late for its author to have met Jesus personally. Nevertheless the John's Gospel and Revelation have much in common: both are written in Greek with Hebrew influence; [18 p.110] they are the only two New Testament books that contain a title within the text; they share ideas and phrases such as calling Jesus "Lamb of God" and "Word of God" [20 p.7]; and both present Jesus as a powerful figure, always in control.
The book is presented as a general pastoral letter to seven churches under persecution on the southern coast of what is now Turkey [20 p.10]. The number seven symbolises perfection [2 p.24] or completeness, implying that the message is actually to the entire church of all ages [20 p.32].
"Revelation is the Bible's 'conclusion' and should be interpreted as such ... Genesis narrates the beginning of mankind's rebellion against God in the Garden of Eden, while Revelation narrates the concluding story of God's eventual triumph over the Evil One and all those the Evil One incites to rebellion". [20 p.29–30] The book begins and ends with assurance that Jesus will come again  and emphasizes his triumph over worldly power [20 p.18], to encourage those whose faith is wavering [20 p.98]. It is worth comparing Revelation with 1 Corinthians 15.
Revelation, like Ezekiel's, Daniel's and Zechariah's prophecies, uses both historical and contemporary symbols; the style is called Apocalyptic writing or Apocalypse. "Apocalypses view reality from an entirely different frame of reference in order to transform our understanding of human existence." [20 p.16] "they should be seen as predicting, or even calling for, great changes in the social order." [2 p.13] Revelation "weaves together imagery from the Old Testament but locates it all in the final saving work of God and the Lamb".
Wilcock [3 p.67] likes Caird's  description of Revelation as a vision of God's control room, where maps are spread out and secret plans for victory are devised. Some features on the maps show the present situation, others what is planned.
Apocalyptic writing traditionally arose from the Merkabah process: a rabbi would fast and pray and seek inspiration. This method was applied to a number of fields, apocalyptic being regarded as the most difficult, so it was left to the most expert rabbis, and even they would base their thoughts on previous apocalyptic works. The results often prophesied the down-fall of the current powers-that-be, which was politically dangerous, so they used coded references to those powers and wrote under pseudonyms. It is hardly surprising that the identity of the author is in doubt. Revelation's message is that faithful witness attracts opposition, but only for a time, and God's eventual victory is assured [2 p.112].
Much of the book is metaphorical, using symbols; some (such as the woman giving birth to a child in chapter 12) have at least six meanings, all apparently intentional, even though some refer to pagan goddesses! Perhaps John deliberately avoided explaining his metaphors to avoid excluding any potential meanings [2 p.16]. Seven Seals are opened by the Lamb, and we read of three groups of seven woes (Seven Trumpets; Seven Plagues; Seven Bowls) associated with human behaviour and the response of nature and God to it. These sevens all culminate in the last judgment, so they seem to tell the same story three times [2 p.16]. Within these "sevens" certain details repeat, for example, a period of 1,260 days (Revelation 11:2). "It is characteristic of ancient texts that they go over the same ground in different ways" [32 p.40].
The fact that details recur suggests that the text describes the same sequence of events more than once in different words, perhaps from a different point of view, to confirm and clarify them, as did Pharaoh's two dreams with the same meaning (Genesis 41:32) [3 p.38–39]. Also the repetition and numbered items would make the text easier to follow for a congregation hearing it read aloud [2 p.17].
Wall [20 p.33f] identifies five ways Revelation chapters 4–22 have been interpreted:
Structure presented by Atkinson 
Structure based on Wilcock [3 p.15f]
† Maxwell  p.92 identifies the first 4 seals with Jesus's prophecies in Mark 13:7–8, and the first 4 trumpets with Mark 13:19–25.
Scene changes based on Wilcock [3 p.114–5]
© David Billin 2002–2021