This manuscript by Jacob ben Asher (son of the rabbi and codifier
Asher ben Jehiel) contains one of the oldest copies of the Jewish
code Arba’ah Turim. The entire work treats all rules of Jewish
law concerning prayers and the synagog. This manuscript contains
only the first of four parts. The main text is surrounded by many
glosses and commentaries; noteworthy is an autograph note by the
influential 15th century German rabbi Jacob Weil in Slavic. The
manuscript offers variant readings to the standard editions and
contains some otherwise unknown Responsa ("rabbinic answers") by
the important Rabbi Israel Isserlin (1390-1460).