God is Heaven and Hell.
The following is taken from St Maximus the Confessor (Quaestiones ad Thalassium, 59), in the early 7th century:
For [human] nature does not have the essential principles [logoi] of what is above nature, just as it doesn't have the laws of what is contrary to nature. Now, by "above nature," I mean the divine and incomprehensible delight that God is naturally apt to produce in the worthy when He is united by grace to them. By "contrary to nature," on the other hand, I mean the lack of this [delight], a lack that establishes an ineffable pain, which God is naturally such as to produce in the unworthy when He is united to them apart from grace. You see, God---united to all as only He knows how---bestows on each man the type of experience of Himself that accords with the quality of each man's settled disposition. He bestows the experience that matches the kind of person each man has become, the kind of vessel he has molded himself into to receive the One whose goal for the end of the ages is to unite himself without remainder to all.