The Miszmorim brotherhood operated at the Jewish hospital, and its task was to help the sick at night, support them with money, tea, sugar and organize services in the small synagogue at the hospital on Saturdays and Jewish holidays. Associated with the Miszmorim Brotherhood in Płock, were, among others, Ber Taub, Rubin Temersohn, Chaim Płońskier, Moszek Aron Sadzawka, Hersz Jakub Zylberberg, Hersz Licht and Laks.
Moszek Aron Sadzawka (1864-1936) – son of Szaja Zajnwel and Gitla nee Granat. His wife was Ryfka Wajcman from Wyszogród. From the beginning of the 1880s, Moszek Aron Sadzawka traded in tobacco products in Płock, and in the interwar period he ran a company selling furniture. He was the owner of the real estate located at Bielska Street. Moszek Aron Sadzawka was a one-man institution, a tireless organizer and activist, involved in various welfare and charity initiatives, including he organized fundraisers for poor brides, he was the treasurer of Gemiłus Chesed, he materially supported the Jewish hospital.
