After the final judgment, there will be a new earth and a new heaven, where everybody who has trusted in Jesus will enjoy God’s presence for all eternity. And the devil will be in hell for all eternity, not as its ruler, but because God will send Him to hell.
In Revelation 20, we read that at the end of time Satan and the people doing his bidding will launch one final rebellion against God. After that “the devil who had deceived them was thrown into the lake of fire and sulphur… and… will be tormented day and night forever and ever” (Revelation 20:10).
So the end of the devil is sure. That actually is one reason why he is so active in trying to destroy God’s children. Revelation 12:12 says about him: “the devil has come down to you in great wrath, because he knows that his time is short!” In the light of eternity, Satan only has a small amount of time to cause us harm. We know that God will have the victory. Let us be on His side!