A herem is a form of social and religious ostracism used by Jewish communities. In Spinoza's case, it was issued against him due to his controversial ideas about the Hebrew Bible and the nature of the Divine. This led to his expulsion from Jewish society at the age of 23, including being shunned by his own family.
Unraveling the Enigma: Dive into the Mind of Baruch Spinoza - The Visionary Dutch Philosopher