Editing Israel Isserlein (section)

===Terumat HaDeshen===
{{See also|History of Responsa#Fifteenth century}}

''Terumat HaDeshen'' is a work in two parts. The first part of is a collection of 354 [[responsa]] by R' Isserlein.
The work is named for the practice in the [[Temple in Jerusalem]] of removing a part of the previous day's ashes from the furnace – 354 is the [[gematria|numerical value]] of ''Deshen'' (Hebrew: '''דשן'''). ''Terumat HaDeshen'' serves as an important source of the practices of the [[Ashkenazi|Ashkenazi Jews]]. The work was therefore used by R' [[Moses Isserles]] as one basis for ''HaMapah''  – the component of the ''Shulkhan Arukh'' which specifies divergences between [[Sephardi]] and Ashkenazi practice.
The second part of ''Terumat haDeshen'', entitled ''Pesakim u-ketavim'', contains 267 decisions largely on points of the marriage law.

According to [[Shabbatai ha-Kohen]] (the "Shach"), it was "known" that Rabbi Isserlein was not answering questions posed to him in the ''Terumat HaDeshen'', rather he actually wrote the questions and answers himself. Therefore (Shach concludes) unlike with other responsa, the parameters of the questions posed in the ''Terumat HaDeshen'' are themselves binding when alluded to in the answer.<ref>Commentary of the ''Shach'' on [[Shulchan Aruch]], [[Yoreh De'ah]] 196:20</ref> However, with the printing of the work ''[[Leket Yosher]]'' of Joseph (Joselein) ben Moses in 1903, it became apparent that the responsa were in fact based on actual questions, as the individuals who asked the questions are clearly identified there.<ref>See ''Leket Yosher'', introduction, p. XIV</ref>