Notes on Book of Exodus (Author Bishop Richard Challoner (ed.))
7:3 I shall harden, etc: not by being the efficient cause of his hardness of heart, but by permitting it; and by withdrawing grace from him, in punishment of his malice; which alone was the proper cause of his being hardened.
Original Douay-Rheims from Project Gutenberg - Massive cleanup of OCR problems and editing done locally.