Revelation

The book of Revelation is the most abused and misunderstood book of the Bible!
The language is purely symbolic. Its rich imagery celebrates the Champion of the Ages, the slain and risen Lamb of God bringing closure to every definition of judgment in his death and resurrection.
Jesus is not a literal Lamb, nor a literal Lion! As the Son of God he is the Incarnate Word that has always been face to face with God. He is the Word in whom all things exist!
The stars are not literal stars neither is the underworld a literal fathomless pit, or the Lake ablaze with Brimstone a literal place!
Throughout the unfolding conversation, pictures come to mind that have already been part of the narrative of God's prophetic dealings with Israel for generations, symbolically pointing to a Person and a Moment recorded historically in time, where the resolve of God concludes powerfully in the glorious triumph of the Lamb over every definition of Devil. In fact, every possible idea of Sin, Judgment, Death, Hades, Satanos, Devil, Demon, Dragon, Beast and False Prophet-Prostitute is addressed and dissolved and thus rendered redundant. See Rev 17:14 These join forces in that hour to wage war against the Lamb, but the Lamb defeats them since he is the Lord of lords and the King of kings. And, sharing with him in his victory, are his kindred, recognizing their origin in this conversation; they too are now of the same persuasion. The Lamb led them into freedom from their lost identity, and their doubts.
As far as God is concerned, it is indeed, Mission accomplished! The salvation of humankind is no longer a possible outcome of events, it is the grandest announcement of the redeemption of the Romance of the Ages!
Rev 20:15 And everything that was not written in the Book of Life was poured into the Lake of fire. (The authentic ID of human life is defined in the Book of Life - or the Tree of Life, representing the redeemed life of our design, versus the alternative Tree of the knowledge of good and evil, representing humanity's identity under scrutiny and questioned. The "I am not-Tree" heads up a system of a works and performance based philosophy, judging the masses of humanity as condemned to eternal torment.
To have your name written in the Book of Life simply suggests that you discover your identity there in the Zoe-life redeemed by the Lamb. You may have only known yourself according to the flesh, as Simon, the son of Jonah, while you really are Petros; Mr Rock, a chip of the old Block! Every evidence of an inferior identity is cast into the lake of Sulphur burning away the dross to reveal the gold! Any idea of an identity outside of the Book of Life, is dissolved! The Lamb's Book of Life and not the law of personal achievement and performance, defines us!)
The book of Revelation is the unveiling of Jesus Christ as the great Rescuer of the human race. As the slain and risen Lamb of God, he fulfilled mankind's destiny with death and judgment! The significance of the implications of this cannot be exaggerated! It reaches into the entire past, present and future of human history!