Revelation 20:1

1AndΚαὶI sawεἶδονan angelἄγγελονdescendingκαταβαίνονταout ofἐκτοῦheavenοὐρανοῦ,holdingἔχονταtheτὴνkeyκλεῖνof theτῆςAbyssἀβύσσουandκαὶa chainἅλυσινgreatμεγάληνinἐπὶtheτὴνhandχεῖραof himαὐτοῦ.

And I saw an angel descending out of heaven, having the key of the Abyss and a great chain in his hand.