From The Discourse On The Resurrection

VII. He says, as was said also by Athenagoras, (1) that the devil is a spirit, made by God, in the neighbourhood of matter, as of course the rest of the angels are, and that he was entrusted with the oversight of matter, and the forms of matter. For, according to the original constitution of angels, they were made by God, in His providence, for the care of the universe; in order that, while God exercises a perfect and general supervision over the whole, and keeps the supreme authority and power over all--for upon...