An important area of Jakub Lewin Szenwic’s activity was charity and involvement in the life of the Jewish community of Płock. Jakub Lewin Szenwic several times (in 1823, 1847, 1850 and 1854) was elected a member of the synagogue supervisory board – the body of the Jewish community’s self-government, which was responsible, among others, for for the balance of revenues and expenses related to the maintenance of the synagogue, the shelter for the poor and the cemetery, as well as collecting fees for religious rites and contributions of members of the Jewish community. In 1834, Jakub Lewin Szenwic became a member of the Committee of the Jewish Hospital of the Płock Province, whose task was to establish a hospital for Jewish patients in Płock. The hospital was established in 1836, and Jakub Lewin Szenwic was one of the people who supported this project financially (at that time the hospital was located in a house at Płońska Street, mortgage number 336). Jakub Lewin Szenwic was also a member of the Bykier Holop burial fraternity, which organized funerals and took care of the area of the Jewish cemetery.
Jakub Lewin Szenwic and his wife Jacheta both died in 1864: on September 17 – Jacheta, on November 1 – Jakub Lewin. According to death certificates drawn up on October 20 and November 2, the couple left four sons: Chaskiel, Natan, Markus and Rudolf, and a daughter, Sura aka Julia, married to Simon Leyzer, a merchant from Toruń. The Szenwic couple were also the parents of Maria, whose husband was Abraham Poznański from Gąbin, Chana Łaja, married to Cohn, the wife of Hersz Mendel, a merchant from Płock, and Rozalia, whose husband was Teodor Shiff.
The main heirs of Jakub Lewin Szenwic were his four sons: Chaskiel, Markus, Rudolf and Natan. Property number 258 letter E and plot number 258 letter D were inherited by Chaskiel, the house with a granary at 88 Piekarska Street and property number 282 – to Markus, property number 257 – to Natan, and property number 495 letter A and 255 – to Rudolf.
