St. Augustine on the creation of the angels

Looking into some of the church fathers views on Genesis, I stumbled across this very interesting interpretation from Augustine. To me it does not seem incongruous with the working of God, if we understand that the angels were created when that first light was made, and that a separation was made between the holy and the unclean angels, when, as is said, “God divided the light from the darkness; and God called the light Day, and the darkness He called Night.” For He alone could make this discrimination, who was able also before they fell, to foreknow that they would fall, and that, being deprived of the light of truth, they would abide in the darkness of pride. St. Augustine City of God Book XI, Chapter 19