The opening verses of Revelation (1.1-3) fill the all-important role of directing the audience’s mind to the topics covered in the book as a whole. The preface (or superscription, as it is sometimes called) of Revelation (1.1-3) effectively fulfills this function by means of an overview of seven broad features. To begin, it states the title of the book (v. 1). Then follow words about the channels used to communicate the book’s contents (v. 1). The content is featured next in an expression that shows this to be the climax of a prophetic line of thought rooted in the OT (v. 1). The time of fulfillment is said to be near (v. 1). There is some elaboration on the method of communicating the message to John (v. 1), who makes a brief allusion to the prophetic process (v. 2). A clear statement of the book’s practical purpose culminates the three-verse preface (v. 3).
From: Revelation 1-7: An Exegetical Commentary by Robert L. Thomas (Chicago: Moody Press, 1992), p. 50.