Book of the Upright: On Kol Nidre

Jacob ben Meir, known as Rabbenu Tam (“the simple,” after the description of the biblical Jacob in Genesis 25:27), was the leading French rabbinic scholar of the twelfth century. A grandson of Rashi and younger brother of Samuel ben Meir (Rashbam), Rabbenu Tam lived in Ramerupt, before fleeing for Troyes after almost being murdered in the Second Crusade of 1147. Rabbenu Tam revolutionized talmudic study and is considered the founder of the Tosafist movement. In addition, he contributed to the study of exegesis and grammar and composed piyyutim. He taught many important scholars and corresponded with rabbinic leaders throughout Europe. Rabbenu Tam was also involved in communal leadership and maintained contacts with Christian nobles.