Quotes from John Mark Ministries
Luther knew his illnesses weren’t natural, but demonically caused:

“Our bodies are always exposed to Satan. The maladies I suffer are not natural, but Devil’s spells.”

Martin Luther said this about doctors who treat demonically caused illnesses as though they are natural:

“Idiots, the lame, the blind, the dumb, are men in whom the devils have established themselves: and all the physicians who heal these infirmities, as though they proceeded from natural causes, are ignorant blockheads….”

The Devil, an expert reverse-physician:

The Devil, it is true, is not exactly a doctor who has taken degrees, but he is very learned, very expert for all that. He has not been carrying on his business during thousands of years for nothing….”