second death
Second death, Summary:
"The second death" and the "lake of fire" are identical terms (Revelation 20:14) and are used of the eternal state of the wicked. It is "second" relative to the preceding physical death of the wicked in unbelief and rejection of God; their eternal state is one of eternal "death" (that is, separation from God) in sins (John 8:21); (John 8:24). That the second death is not annihilation is shown by a comparison of (Revelation 19:20); (Revelation 20:10).
After one thousand years in the lake of fire, the Beast and False Prophet are still there, undestroyed. The words "forever and forever" ("to the ages of the ages") are used in (Hebrews 1:8) for the duration of the throne of God, eternal in the sense of unending.