Version #1 - Question (Rav Bivi bar Abaye): If Reuven stuck a dough in an oven on Shabbos, may he remove it before it bakes, to avoid a Chiyuv Chatas?

Question (Rav Acha bar Abaye): What is the case?

If he put it in b'Shogeg and is still Shogeg, the law is irrelevant (he is unaware of any transgression, surely he will leave it in!)

Answer #1: Rather, he put it in b'Shogeg and later remembered.

Objection: If so, he cannot be Chayav Chatas!

(Mishnah): One is not Chayav Chatas unless he was Shogeg at the beginning and at the end.

Answer #2: Rather, he was Mezid.

Objection: If so, it should say '...To avoid an Isur Skilah (stoning)'!

Answer #3 (Rav Shila): Really, he was Shogeg;

Rav Bivi's question was whether or not someone else [who knows that Reuven is transgressing] may remove it to exempt him.

Objection: One may not sin (even mid'Rabanan) in order to save someone else from sin!

Defense of Answer #2 (Rav Ashi): Really, he was Mezid; it should say 'To avoid an Isur Skilah.'

Version #2 - Rav Acha brei d'Rava - (Rav Bivi bar Abaye): If Reuven stuck a dough in an oven on Shabbos, he may (Tosfos - some texts say 'may he', it is a question) remove it, to avoid an Isur Skilah.

(Mishnah): If the Oni put his hand inside...[and put an object in the hand of the Ba'al ha'Bayis, he is Chayav].

Question: Why is he Chayav? Akirah and Hanachah must be from [and on] a place that is four by four [Tefachim; a hand is much smaller]!

Answer #1 (Rabah): The Mishnah is like R. Akiva, who does not require a place that is four by four:

(Mishnah - R. Akiva): If one throws from a Reshus ha'Yachid to another Reshus ha'Yachid and Reshus ha'Rabim is in between, he is liable;

Chachamim exempt.

R. Akiva holds Kelutah k'Mi she'Hunchah (something in the air is considered to be at rest), Chachamim do not say Kelutah k'Mi she'Hunchah.

Question: This implies that Rabah is sure that the case is (that he threw) within 10 Tefachim of the ground, and they argue about Kelutah k'Mi she'Hunchah - but he was unsure about this!

Question (Rabah): In what case do they argue?

Perhaps they argue within 10 Tefachim, whether or not Kelutah k'Mi she'Hunchah, but all exempt above 10, no one learns throwing from Moshit (passing an object from one Reshus ha'Yachid to another, through Reshus ha'Rabim);

Or, they argue above 10 Tefachim, R. Akiva learns throwing from Moshit, Chachamim do not - but all Mechayev below 10, Kelutah k'Mi she'Hunchah.

Answer: Rabah later answered his own question (they argue below 10.)

Rejection: Perhaps R. Akiva does not require Hanachah on a place that is four by four, but he requires Akirah from a place that is four by four:

Answer #2 (to Question (b) - Rav Yosef): Our Mishnah is like Rebbi.

Question: Like which teaching of Rebbi is it?

Answer #1 (Beraisa - Rebbi): If one threw something [in Reshus ha'Rabim] and it landed on a ledge of any size, he is liable;

Chachamim exempt.

Rejection: No - Abaye explained, the Beraisa discusses a tree in Reshus ha'Yachid, its foliage hangs into Reshus ha'Rabim, the thrown object landed on the foliage;

Rebbi applies the status of the trunk (Rashi - it is four by four; Tosfos - and it is Reshus ha'Yachid) to the foliage, Chachamim do not. (Tosfos ha'Rosh - just like Abaye taught that Rebbi considers the foliage to be Reshus ha'Yachid on account of the trunk, we can say that Rebbi considers the foliage to be four by four on account of the trunk.)