While angels have played a decisive role in all the world's major religions and continue to loom large in the popular religious and creative imagination, modern theology has tended to ignore or trivialize them. The comparatively few scholarly works on angels over the last century have typically interpreted them as mere symbols and metaphors: they are said to offer glimpses not of the divine order, but of human desires, anxieties, and ideologies. Angelology has collapsed into anthropology. By contrast, this polemical book argues for the indispensable importance of studying angels as divinely created beings, for theology at large, and for understanding the defining doctrine of monotheistic religions in particular. Additionally, the book contends that the spirit of modern science did not originate with the so-called Scientific Revolution but was actually inspired centuries earlier by the angelological lucubrations of medieval scholastics.