Then Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire.
The utter destruction of the devil's kingdom very properly leads to an account of the day of judgment, which will determine every man's everlasting state; and we may be assured there will be a judgment when we see the prince of this world is judged, Joh 16:11. This will be a great day, the great day, when all shall appear before the judgment-seat of Christ.
Commenting on Revelation 20:11-15
And death and hell were cast into the lake of fire,.... Death cannot be taken properly, nor hell be the place of torment, for devils and damned spirits; since that is that lake of fire, for then the sense would be, hell is cast into hell; but either by these the devil is meant, who has the power of death, and is the prince of...
Verse 14. And death and hell were east into the lake of fire. Death and Hades (hell) are here personified, as they are in the previous verse. The declaration is equivalent to the statement in , "The last enemy that shall be destroyed is death." . The idea is, that death, considered as the separation of soul and body, with all the attendant woes, will exist no more.