Apokatastasis, restoration, is the hope that in the end all creatures, perhaps even the devil, will be restored to union with God. Origen taught a form of it, and Gregory of Nyssa spoke of God becoming all in all. Origen’s teaching was later condemned, but the hope has recurred in Christian thought.
Apokatastasis
The final restoration of all things to God, taught by Origen and Gregory of Nyssa.
Also: universal restoration