Revelation 9:1

AND the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.

‘A star fall from heaven’ signifies the Satanic force released in the sounding of the fifth trumpet. Satan and his servants can only fall to greater depths of spiritual darkness when released from their divine constraints. That the ‘key of the bottomless pit’ was given to the ‘star’ marks him to be the one later mentioned to be the king over the army released in the opening of the ‘bottomless pit’, and referred to as ‘the angel of the bottomless pit’: “And they had a king over them, which is the angel of the bottomless pit, whose name in the Hebrew tongue is Abaddon, but in the Greek tongue hath his name Apollyon.” (Revelation 9:11) Abaddon and Apollyon in the Hebrew and Greek tongues mean destroyer. Since Satan is the ultimate destroyer he is ‘the angel of the bottomless pit’. Peter likened the devil to a roaring lion seeking whom he may devour, “Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour:” (1 Peter 5:8)

The ‘bottomless pit’, a pit without a bottom, is symbolic of immeasurable spiritual darkness, the spiritual abode of fallen angels - hell. The apostle Peter pointed out that God had cast the angels that sinned down to hell, and delivered them into chains of darkness, “For if God spared not the angels that sinned, but cast them down to hell, and delivered them into chains of darkness, to be reserved unto judgment;” (2 Peter 2:4) Hell, like a pit without a bottom, is endless and never full. Solomon wrote, “Hell and destruction are never full; so the eyes of man are never satisfied.” (Proverbs 27:20) The ‘key of the bottomless pit’ signifies the authority to open hell and to release the powers of darkness which reside there.

In the sounding of the fifth trumpet, therefore, Satan will be released to be given the authority over immeasurable spiritual darkness and to release the powers of darkness therein.