הרב יעקב בן אשר

Harav Jacob ben Asher, known as the author of the Arba’ah Turim and the Ba’al Haturim – a numerically focused commentary on the Torah (הרב בעל הטורים), was a Rishon whose great halachic code arranged the law across four major divisions and became one of the central pillars of practical halachah. He is the son of the Ro”sh, and lived his early years in Cologne, Germany, but left for Spain to escape the persecution of Jews there, where he lived until his death (1343 in Toledo, Spain).

The Tur, written in the late 1200s CE is extensively commented on by the Beit Yosef (Maran) and the Ba”ch, who are the “nosay keilim” for this important codification of the halachah. The Beit Yosef follows the chapters and discussion of the Tur as the basis for the seminal Shulchan Aruch, which is considered our modern footprint (written in the 1500s CE) for all Halachah consideration.