Gershom Ben Judah - Synod and Bans

Synod and Bans

He is famous for his religious bans within Judaism, which include:

• The prohibition of polygamy (until the end of fifth millennium (1240 CE) according to some opinions; others find no mention of this in the early sources and therefore hold it is still in force);
• The prohibition of divorcing a woman against her will;
• The modification of the rules concerning those who became apostates under compulsion;
• The prohibition of reading private mail.

His bans are considered (by Orthodox Jews) to be binding on all of Ashkenazic Jewry until the present day, although the reasons for this are controversial. Some authorities hold that the bans are still binding, while others consider them to have expired but nonetheless obligatory to follow as universally accepted customs.