16 We want to know whether souls, before man was made in paradise, and Adam was fashioned out of the earth, were among reasonable creatures; whether they had their own rank, lived, continued, subsisted; and whether the doctrine of Origen is true, who said that all reasonable creatures, incorporeal and invisible, if they grow remiss, little by little sink to a lower level, and, according to the character of the places to which they descend, take to themselves bodies.
(For instance, that they may be at first ethereal, afterward aërial.) And that when they reach the neighbourhood of earth they are invested with grossest bodies, and last of all are tied to human flesh; and that the demons themselves who, of their own choice, together with their leader the devil, have forsaken the service of God, if they begin to amend a little, are clothed with human flesh, so that, when they have undergone a process of repentance after the resurrection, and after passing through the same circuit by which they reached the flesh, they may return to proximity to God, being released even from aërial and ethereal bodies; and that then every knee will bow to God, of things in heaven, and things on earth, and things under the earth, and that God may be all to all.
When these are the real questions, why do you pass over the points at issue, and, leaving the arena, fix yourself in the region of remote and utterly irrelevant discussion?
Source: To Pammachius Against John of Jerusalem (New Advent)