God only speaks twice directly to the reader in Revelation, Craig Koester points out (Revelation and the End of All Things, 51). He says the same thing both times: “I am the Alpha and the Omega . . . who is and who was and who comes, the Almighty: (1:8; 21:5-8).
It makes a neat inclusio around the book as a whole, an inclusio that is about inclusio, the divine inclusio that encloses the chaism of human history.
Koester finds theological significance in this: “If God is the beginning and God is the end, then God is the focus of the book. The point is significant. The book does not say that the four horsemen are the beginning and the great judgment is the end, but that God is the beginning and God is the end” (52).
He reinforces this later: “To use the words of Revelation itself, the End of all things is God and the Lamb. What is startling about this disclosure is that it brings us back to where we began. Readers are like travelers, who climb mountains and cross valleys, who swelter in the day and grope through the darkness at night, contending with plagues, tyrants, and wild beasts only to find themselves back on their front doorstep, looking at the view with new eyes.” What God and Jesus say at the beginning of the book shows “readers the implications of what it means to know that ‘the end is not an event, but a person’” (quoting GB Caird, 172).