Nicene and Post-Nicene Fathers, Vol. V:
A Treatise on the Soul and its Origin.: Chapter 16

Chapter 16.—God Rules Everywhere: and Yet the “Kingdom of Heaven” May Not Be Everywhere.

You may, however, not improbably contend that all things, it is true, belong to the kingdom of God, because He reigns in heaven, reigns on earth, in the depths beneath, in paradise, in hell (for where does He not reign, since His power is everywhere supreme?); but that the kingdom of heaven is one thing, into which none are permitted to enter, according to the Lord’s own true and settled sentence, unless they are washed in the laver of regeneration, while quite another thing is the kingdom over the earth, or over any other parts of creation, in which there may be some mansions of God’s house; but these, although appertaining to the kingdom of God, belong not to that kingdom of heaven where God’s kingdom exists with an especial excellence and blessedness; and that it hence happens that, while no parts and mansions of God’s house can be rudely separated from the kingdom of God, yet not all the mansions are prepared in the kingdom of heaven; and still, even in the abodes which are not situated in the kingdom of heaven, those may live happily, to whom, if they are even unbaptized, God has willed to assign such habitations. They are no doubt in the kingdom of God, although (as not having been baptized) they cannot possibly be in the kingdom of heaven.