Revelation 17:9-11

The Great Prostitute and the Beast

⁹ _v This calls for a mind with wisdom: the seven heads are seven mountains on which the woman is seated; ¹⁰ they are also seven kings, five of whom have fallen, one is, the other has not yet come, and when he does come he must remain only a little while. ¹¹ As for the beast _w that was and is not, it is an eighth but it belongs to the seven, and it goes to destruction.

1. Cross References
   Revelation 13:18
   This calls for wisdom: let the one who has understanding calculate the number of the beast, for it is the number of a man, and his number is 666.
   
2. Cross References
   Revelation 17:8
   The beast that you saw was, and is not, and is about to rise from the bottomless pit and go to destruction. And the dwellers on earth whose names have not been written in the book of life from the foundation of the world will marvel to see the beast, because it was and is not and is to come.
   Revelation 11:17
   Saying, "We give thanks to you, Lord God Almighty, who is and who was, for you have taken your great power and begun to reign.