Most Relevant Verses
and he threw him into the abyss, and shut it and sealed it over him, so that he would not deceive the nations any longer, until the thousand years were completed; after these things he must be released for a short time.
They have as king over them, the angel of the abyss; his name in Hebrew is Abaddon, and in the Greek he has the name Apollyon.
More Verses on Abyss
"The beast that you saw was, and is not, and is about to come up out of the abyss and go to destruction And those who dwell on the earth, whose name has not been written in the book of life from the foundation of the world, will wonder when they see the beast, that he was and is not and will come.