Revelation 8:5

And the angel took the censer, and filled it with fire of the altar, and cast it into the earth: and there were voices, and thunderings, and lightnings, and an earthquake.

The angel being shown to cast ‘fire of the altar’ into the earth signifies the end of the intercession for the saints and the crossing of the line of no return in which forgiveness will no longer be available to those who repent. At this point the wicked will have no other option but to remain in their sins. Ezekiel also placed the casting down of fire to happen after the sealing: “And the LORD said unto him, Go through the midst of the city, through the midst of Jerusalem, and set a mark upon the foreheads of the men that sigh and that cry for all the abominations that be done in the midst thereof.”(Ezekiel 9:4) After the man had done as the Lord commanded, he was instructed to scatter coals of fire over the city: “And he spake unto the man clothed with linen, and said, Go in between the wheels, even under the cherub, and fill thine hand with coals of fire from between the cherubims, and scatter them over the city.” (Ezekiel 10:2)

‘Voices, and thunderings, and lightnings’ which once denoted the presence of the Lord on Mount Sinai, signify the manifestation of the Spirit of the Lord in the redemption of the ‘great multitude’.