Notes on The Epistle of St. Paul to the Ephesians (Author Bishop Richard Challoner (ed.))
6:12 High places: or heavenly places. That is to say, in the air, the lowest of the celestial regions; in which God permits these wicked spirits or fallen angels to wander.
Original Douay-Rheims from Project Gutenberg - Massive cleanup of OCR problems and editing done locally.