Brachot 6 - Demons
Abba Binyamin taught that there are many demons, invisible spiritual agents, and if an eye could see them, no creature would be able to stand in face of them. Abaye added "They outnumber us." Rava said, "The feeling that one is squeezed at a public lecture - it's because of them. The garments of the students who only study and do no hard work, when they wear out fast - it's because of them." If one wants to see their steps, let him take sifted ashes and spread them around his bed, and in the morning he will see marks like the footprints of a rooster. If one wants to see them, he should take a placenta of a female cat, that is a black cat, daughter of black cat, burn it, grind it, and put it in his eyes. He should hide the ashes in lead, and the whole practice is dangerous and not recommended.
God wears tefillin, as it were. What is written in them? "Who is like your people Israel." But is the Holy One Blessed He praised with the praises of Israel? - Indeed, yes, as the Torah said, " You have praised God today, and He praised you ."
One who knows that his friend is accustomed to greet him, should greet his friend first, following the dictum of "Seek peace and pursue it." If someone greets him, and he does not return the greeting, he is called a robber, as Isaiah said, "Property robbed from the poor is in your houses." Why is "poor" mentioned? One should not steal from the rich either! - To tell us that he steals from a destitute, who does not have any possessions, and what he steals is a greeting.
Art: Henriette Ronner-Knip - A black cat