If Porutz Meruba is Halacha L'Moshe M'Sinai, how were the Rabanan matir it for pasei biroyos for olei regalim?
pinchos berman, Baltimore, United States
Dear Pinchos,
Tosfos DH Osin on Eruvin 17b asks your question and answers that when there is Shem Arba Mechitzos then Parutz Meruba is only forbidden midRabanan and Pasei Biraos has in each corner an Ama in each direction and that is enough to be called Shem Arba Mechitzos .
The Raavad however learns that Poretz Meruba is always only d'Rabanan- and the expression of Rachmana is because even future Gezeros of the Chachamim were revealed to Moshe on Sinai.
All the best,
Reuven Weiner