How does the Rambam interpret this rule since he holds that by a Safek Deraissa we go LeKulah Mideraissa. Thank you.
Jeno Gal, Toronto
The Rambam probably learns like Rashi and Tosfos in Sanhedrin (79a, Rashi DH "Lo Tzericha" and Tosfos DH "v'Chol Kavua") that the source of this law is a Gezeiras Ha'Kasuv from the Pasuk, "v'Arav Lo v'Kam Alav" (as implied by the Gemara there). If this is the case, it is not like a regular case of Safek which does not have a Gezeiras ha'Kasuv of its own.
All the best,
Yaakov Montrose