I was learning this sugya in yeshiva (the ran), and my rebbe wasn't able to answer the question of if the ed is boosted, but not to the level of 2 aidim, so why does abayie hold that ed echad in regards to davar shebierva works? (my chavrusa suggested that maybe abayei holds that the ed gets boosted to 2 adim, unlike rava. Is that right maybe?)
Scott Sears
East Windsor, NJ, US
The Rishonim ask this question and give various answers, some of which are viable for the Ran's Pshat.
(a) The Rashba says that Abayei holds that the Din of Ein Davar she'b'Ervah Pachos mi'Shnayim is only when there is Hacchasha. The Ran also seems to adhere to this opinion.
(b) The Rashba offers a further option, that since in other Isurim (which are not Davar she'Bervah) an Eid Echad is sufficient, Abayei holds that we must be Machmir even in a Davar she'Bervah, mi'de'Rabanan.
(c) The Tosfos Rid says that Abayei disagrees with the whole concept of Ein Davar she'b'Ervah Pachos mi'Shnayim.
(d) Tosfos (Amar Abayei) hold that according to Abayei the Din Ein Davar she'b'Ervah Pachos mi'Shnayim only applies when a Kiyum is necessary, and for a lady to become forbidden to her husband through adultery no Kiyum is required, so we do not need two Eidim.
Dov Freedman