Revelation 19:20

And the beast was taken, and with him the false prophet that wrought the signs in his sight, wherewith he deceived them that had received the mark of the beast and them that worshipped his image: they two were cast alive into the lake of fire that burneth with brimstone:

And the beast was taken ... and the false prophet ... The false prophet (the harlot, the land-beast; all three terms refer to the same thing) was destroyed in the judgment scene of chapter 18, and the mention of the same thing being done here, under a different figure, is merely to show that this judgment is exactly the same as that.

They two were cast alive into the lake of fire ... There is no way to understand a statement like this as being anything else except a reference to the final judgment of the wicked as foretold by Christ (Matthew 25:41). Note that the destruction of the harlot, here called the false prophet, shall be simultaneous with the destruction of the scarlet sea-beast of Revelation 13:1. This means that apostate Christianity will not perish before the final judgment. Both the harlot and the sea-beast (in the form of his eighth head) will be alive and doing a flourishing business when the end comes. Earle likewise stressed the truth that the two beasts of chapter 13 are the same as the beast and the false prophet here.[59] We have also identified the harlot with the second beast (land-beast). Note that John says nothing here of any "battle." "He may mean that there was no battle."[60] Of course, he could hardly mean anything else. And the wrath of the Gentile unsmote by the sword Hath melted like snow in the glance of the Lord!

[59] Ralph Earle, op. cit., p. 608.

[60] Leon Morris, op. cit., p. 232.