"The Jews were at the mercy not only of the monarch but also of the man in the street. My grandfather still wore the obligatory and discriminatory Jewish garb, and in his time every Jew might expect to be hit on the head by any Moslem whom he happened to pass. This pleasant ritual even had a name – the chtaka; and with it went a sacramental formula which I have forgotten."
January 1, 1970
https://en.wikiquote.org/wiki/Albert_Memmi