Dr. Sorin Tumanians, a prominent Iranian physician, in his 1934 Hygiene in the Religion on Islam explained:
The Founder of the religion of Islam was well aware of the existence of microbes and knew how they penetrate the body . . . when he wanted to remind the people of the hygienic ordinances and . . . to instill fear in their hearts so that they would obey these laws, in his pronouncements he used the names of jinn and devil instead of microbes.
While the equivalence of jinns and microbes had been asserted by earlier thinkers, as a licensed physician, Dr. Tumanians provided detailed microbiological explanations for questions of “purity and filth” (taharah va nijasat), questions which had been conventionally elucidated by Shi‘i mujtahids in their responsa (tawzih al-masa’il or risalah ‘amaliyah). Along with the commentary of large cadres of health workers and social critics, Dr. Tumanians’s intervention not only consolidated the transformation of the idea of “purity” (taharat) into “hygiene” (nizafat) and that of “impurity” (nijasat) to “dirty”/unhygienic (kisafat), it also contributed to what I am calling the Pasteurization of Islam (Islam-i pasturizah). This was a movement that was fundamental to the emergence of an embodied political Islam in the 1940s and beyond. This Pasteurian Islam, I argue, was crucial to the revolutionary discourse in the decades prior to 1979 Iranian Revolution.