14 Then Death and Hades were cast into the lake of fire. This is the second death. 15 And anyone not found written in the Book of Life was cast into the lake of fire. (Revelation 20:14–15, NKJV)
Death and Hades will be overpowered and destroyed at the resurrection of the dead (1 Cor. 15:26). At the resurrection and judgment day, Christ (who has “the keys of Hades and of Death,” Rev. 1:18) will destroy death and the grave, fulfilling the prediction that “death will be swallowed up in victory” (1 Cor. 15:54-55). The “lake of fire” is the “second death,” the place of eternal punishment where the devil and his cohorts “will be tormented day and night forever and ever” (Rev. 20:10). Death will never claim another body. Hades will never hold another departed spirit. On the judgment day they will “die” – forever separated from the power and fear they have exerted against humanity. The “second death” has no power over those who have part in the “first resurrection,” for they share in Christ’s victory over sin and death (Rev. 20:4-6; 6:9-11). However, those who are not saved in Christ are not in the Book of Life. Their judgment will be the lake of fire, the second death. Hell is real. Hell is forever punishment, eternal separation from God and all this is good. It is outer darkness, filled with weeping and gnashing of teeth (Matt. 25:30; Mk. 9:43-48). Knowing these things beforehand should compel us by faith to repent and follow Jesus completely.