Question:
We were undecided about the reckoning of time after the millennium. In Revelation 20:10, it talks about “day and night”—is this literal or figurative?

Answer:
We are told in Revelation 20:1-3 that: “the dragon, that old serpent, which is the Devil, and Satan” will be bound in the bottomless pit for a thousand years: “and after that he must be loosed a little season.”

“And when the thousand years are expired, Satan shall be loosed out of his prison,

and shall go out to deceive the nations which are in the four quarters of the earth, Gog and Magog, to gather them together to battle: the number of whom is as the sand of the sea. And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them” (verses 7-9).
Then Revelation 20:10 tells us: “And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet are, and shall be tormented day and night for ever and ever.”
Therefore, having done his final work on earth, the devil is consigned to the judgment God had prepared for him: the lake of fire. Its duration is uninterrupted and eternal. “Day and night” is probably not describing what we now experience but, indeed, the uninterrupted judgment of God just as “for ever and ever” describes it as never ending. God often uses language that we understand so that we can have some understanding when He speaks of eternal things.
After this, the wicked dead stand in resurrection at the Great White Throne. They are judged according to their works and are consigned to the same judgment, the lake of fire, where they are under the wrath of God without interruption or end.
After this, God creates a new heaven and a new earth. Briefly, this amounts to a fixed state of holiness for all creation. Then the tabernacle of God is with men and He dwells among them without interruption or end, and time ceases to be measured. See Ephesians 2:7 for something about this.