The article examines the modesty campaigns led by Neturei Karta circles in the period 1938-1974 under the leadership of Rabbi Amram Blau (1896-1974). This study was made possible following the discovery of Blau's personal archive. It explores the defensive stage of the modesty campaign that was aimed mostly to strengthen the Haredi enclave and to separate it from secular Jerusalem with the establishment of the modesty patrols. It discusses the offensive campaign with the examination of the struggle against mixed swimming pools and against a club operated by Working Mothers' organization. The second stage was intended mainly to reinforce Neturei Karta's leadership position among the Haredi public in Jerusalem. It explores the zealotry ethos in the context of the torching of the Eros sex shop in Jerusalem.