These 3 opening verses set the stage for our understanding of this book as a whole. The points will appear as questions that I hope will help us understand in a general (but Biblical) sense what in the world Revelation actually is. 1. What is an apocalypse? 2. Who’s the author? 3. Who’s the audience? and 4. Is this authoritative? The answers to these questions provided by the passage will help us see ultimately that this is a message for everyday (not just the future) from King Jesus to His church, absolutely including us. 
Revelation 1:1-3