A New Heaven and Earth.
Scripture puts forward the hope that Heaven and earth will be made new (Isa. 65:17, 66:22, Rom. 8:19-21, 2Pet. 3:13, Rev. 21 &22). “The earth will be filled with the glory of the Lord’s “(Num. 14:21, Isa. 11:9, Hab. 2:14) and “God will be all in all.” (1 Cor. 15:28).
If there is at least one corner of this universe that exists forever in rebellion against him, this vision will never be fulfilled. If the wicked are to tormented for all of eternity how can it ever be said that there will be “no more death or mourning or crying or pain, for the old order of things has passed away” (Rev. 21:4).
Conditional Immortality in teaching that the wicked will be finally destroyed and will be as if they have never been (Obad. 1:16) teaches the final fulfilment of this vision!