Commentary for Avodah Zarah 52:15

There are types of people who may actively be murdered. It is hard to know exactly who these people are, especially what the difference between “heretics” and “apostates” is. There are also other versions of this list. “Informers” seems to be akin to what we call “traitors” a crime that is still considered extremely serious and for which one can be executed or jailed for an extremely long time.

R. Yohanan instructs that the baraita recited in front of him be emended. R. Yohanan says that one must return a lost object to an apostate. This shows that he is “your brother.” How then could we say that he must be cast down into a pit? The baraita must therefore be emended.

The Talmud asks why we didn’t resolve the contradiction between the two sources. Why did we not say that one must return a lost object to an apostate who eats carrion (meat which had not been slaughtered properly) just because he is hungry, but not to one who eats carrion meat to provoke, because he simply enjoys transgressing?
The resolution is that R. Yohanan considers one who eats carrion to provoke to be a heretic, a word already included in the baraita. “Apostate” must mean one who eats carrion because he is hungry. Therefore the word must be erased.

According to one opinion, an “apostate” is one who sins because it makes life easier (for instance, it is cheaper to eat non-kosher meat). A “heretic” is one who sins because he wants to provoke (i.e. two hamburgers are put in front of them, one kosher one not, and they eat the non-kosher one). To the other opinion, the term “apostate” includes both categories of sinners. According to this view a “heretic” is a Jew who goes so far as to worship idols.

One probably does not eat a flea or a gnat because one is hungry. Not much nourishment there. One eats a small bug does so only to provoke—because it is forbidden. This seems to prove that even one who sins in order to provoke is still an apostate and not a heretic. The Talmud rejects this and suggests that the person may have eaten the bug neither to provoke nor to feed his hunger. He may have just been curious as to what a forbidden thing tastes like.

The baraita seems superfluous—if you can cast these people in, then obviously you do not need to bring them up.
R. Joseph b. Hama reads into the baraita a broader meaning of the lack of an obligation to bring them up. If one of these people is in the pit, one can even remove the ladder and provide some excuse as to why one is doing so.

These other amoraim read other things in to the baraita that one may do to make sure this person stays in the pit and to provide excuses as to why he is doing so.

In this baraita the sages and R. Meir disagree whether a non-Jew may circumcise a Jew—R. Meir prohibits because he fears murder, while the other sages say that as long as precautions are taken, it is permitted.

In a case where the circumcision can be done only by a non-Jew or a Samaritan (a group similar to the Jews, but with a different center of worship), R. Meir says that the non-Jew should circumcise and not the Samaritan. This is probably because the Samaritan has the wrong intent, whereas the non-Jew has no intent. R. Judah allows the Samaritan but not the non-Jew, probably because the Samaritan is in some ways a Jew. In any case, this proves that R. Meir does allow a non-Jew to circumcise a Jew.

The Talmud solves the problem by reversing the positions in the baraita—now R. Meir holds that a non-Jew cannot circumcise. This is a trick the Talmud pulls occasionally. It usually leads to subsequent problems.

The problem is that now that we have reversed the positions in the baraita, R. Judah seems to hold that a non-Jew may circumcise. But this directly contradicts another statement of his.

The Talmud reverses the positions back to their original arrangement. Now we have to solve the contradiction in the positions of R. Meir. The answer is that to R. Meir it depends on whether the doctor is an expert.