In the beginning of the second half of Satan in Goray, at the wedding of Reb Itche Mates and Rechele, the following scene appears:
Before covering the bride's head he recited an interminable prayer. Rechele cried out only once. When Itche Mates covered her head, a rain of raisins and almonds fell on her, and all the women sobbed and blew their noses. The fool stood on tiptoe at the door so as to be seen, despite his smallness, and chanted in a melancholy way:
"The haidamaks slaughtered and martyred us.
They murdered young children, they ravished women
Chmelnicki slit open bellies, he sewed cats inside, (because of our sins!).
This is why we wail so loudly and implore
Revenge, O Lord, the blood of thy slaughtered saints!"
A woman suddenly fainted, and they poured water over her. A boy suffocating in the crowd screamed in fright. Someone stumbled over the water tun. A vessel broke.
Satan in Goray, part 2, chapter 1: "The Wedding" (translated by Jacob Sloan)
Why does the fool recite this rather depressing verse at a wedding? What relevance does this plea for revenge have to the occasion?