The principle therefore of the soul is not according to Plato in the brain, but according to Christ in the heart, and by this passage we may refute those who think that evil thoughts are suggestions of the Devil, and do not spring from our proper will. The Devil may encourage and abet evil thoughts, but not originate them. And if he be able, being always on the watch, to blow into flame any small spark of thought in us, we should not thence conclude that he searches the hidden places of the heart, but that from our manner and motions he judges of what is passing within us.
For instance, if he see us direct frequent looks towards a fair woman, he understands that our heart is wounded through the eye.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).