DEMONS!!

Babylonian Talmud: Tractate Berakoth

Folio 6a

It has been taught: Abba Benjamin says, If the eye had the power to see them, no creature could endure the demons. 

Its fashionable to say that he is talking about microbes -- only what the Talmud says next doesn't apply to microbes. I think we have no choice but to say that Abba  Benjamin believed in real demons. 

Abaye says: They are more numerous than we are and they surround us like the ridge round a field. R. Huna says: Every one among us has a thousand on his left hand and ten thousand on his right hand.

This is a super remark by R. Huna, who is disagreeing with Abaya in two ways. First,  R. Huna is saying that there are "only" a few thousand demons. And, better yet, they can't hurt you! His words are a clear reference to Psalm 91:7 which reads:

Though a thousand fall at your side,
ten thousand at your right hand,
near you it shall not come.

Raba says: The crushing in the Kallah lectures comes from them. Fatigue in the knees comes from them. The wearing out of the clothes of the scholars is due to their rubbing against them. The bruising of the feet comes from them. 

Rabba is listing things that have no obvious cause. If you sit at your desk all day, why do your clothes wear out? If you don't move around, why do your joints ache? And where did those bruises on your feet come from? Some interpret the Kallah "crush" as ordinary jostling, but I think it had to have been a real Mecca-during-Haj style stampede. Jostling we can blame on the guy doing the pushing and shoving. A stampede, by definition, has no direction or purpose. It just starts, seemingly on its own, which to Rabba suggests a demon's mischief. 

If one wants to discover them let him take sifted ashes and sprinkle around his bed, and in the morning he will see something like the footprints of a cock. If one wishes to see them, let him take the after-birth of a black she-cat, the offspring of a black she-cat, the first-born of a first-born, let him roast it in fire and grind it to powder, and then let him put some into his eye, and he will see them. Let him also pour it into an iron tube and seal it with an iron signet that they should not steal it from him. Let him also close his mouth, lest he come to harm. R. Bibi b. Abaye did so, saw them and came to harm. The scholars, however, prayed for him and he recovered.
This potion recipe isn't, shall we say,  one of the highlights of the Talmud Bavli. 

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