i don't understand R. Meir's answer here (and elsewhere). what does it mean - not to forget the Torah of Eiruv? Either it's needed or not. Why is not forgetting it an issue at all?
Tuvya Marcus, Jerusalem, Israel
The enactment of Eruvin is one of the most important Takanos d'Rabbanan (it was actually initiated by Shlomo ha'Melech). Consequently, where an Eruv (or Shituf Mavo'os) already exists, the Chachamim took great pains to ensure that it should remain intact, so that the children who reside in that particular Chatzer should not forget what it is.
B'Virchas Kol Tuv,