Gemara

A Nochri climbed a date tree and took a Lulav. On his way down, the end of the Lulav accidentally touched wine.

Rav: The wine may be sold to Nochrim.

Rav Kahana and R. Asi: You yourself said that a one day old Nochri makes Yayin Nesech (if he touches wine, even though he has no intention)!

Rav: I meant only that one may not drink it, but one may benefit from it.

Question (against Rav - Rav Simi bar Chiya - Beraisa): Nochri slaves that were circumcised but did not yet immerse, and similarly Bnei Shifchos (children of a Yisrael's female slave; she did not yet immerse to become a Shifchah Kena'anis) that were circumcised but did not yet immerse:

Their spit and Medrasan (what they step on) are Teme'im (mid'Rabanan, they are like Zavim, even) in the market;

Some say, their spit and Medrasan are Tehorim.

Adults make Yayin Nesech, but children do not;

'Adult' refers to one who knows idolatry well. 'Child' is one who does not.

Answer: The Seifa (that distinguishes children from adults) discusses Bnei Shifchos. (They will be raised in the Yisrael's house, unlike a Nochri child.)

Question: It says similarly (Bnei Shifchos... This implies that the law is the same as for slaves who did not yet immerse, i.e. Nochrim!)

Answer #1: Their law is the same for Tum'ah.

Question: According to the opinion that spit and Medrasan of Nochrim are Tehorim, how can we answer?

Answer #2: It teaches that slaves born to Nochrim are like Bnei Shifchos. They make Yayin Nesech before immersing, but not afterwards.

This is unlike Shmuel, who said that if one buys slaves from a Nochri, even after they are circumcised and immerse, they make Yayin Nesech until their (previous) connection to idolatry is forgotten.

Question: How long is this?

Answer (R. Yehoshua ben Levi): It is 12 months.

57b: According to the opinion that spit and Medrasan of Nochrim are Tehorim, Shmuel must explain the Beraisa to teach that regular slaves (before immersing) are like Bnei Shifchos. Only adults make Yayin Nesech, but children do not, unlike Rav.

Rishonim

Rif: Some say that the Halachah follows Rav, for the Halachah follows him (against Shmuel) in Isurim. Some say that the Halachah follows Shmuel, for R. Yehoshua ben Levi explains his teaching.

Ran (DH Ela): Presumably, Shmuel requires that the slaves cease to mention idolatry only if they were forcibly circumcised and immersed. If they did so willingly, they are immediately considered Yisraelim. Shmuel agrees that we decree about an adult Nochri who touched without intent, lest people say that he intended to touch, and even so Chachamim permitted. He argues only about a baby, for we need not decree about a baby.

Rambam (Hilchos Ma'achalos Asuros 11:5): If a Nochri touched wine without intent, or a Nochri child touched wine, one may not drink the wine, but one may benefit from it. If one bought slaves from a Nochri and they circumcised and immersed, immediately they do not make Yayin Nesech. One may drink wine that they touched, even though they do not yet follow laws of Yisrael and they still mention idolatry.

Rosh (4:5): Rashi's text says that the end of the Nochri' Lulav accidentally touched wine. R. Tam challenged this. How can we compare what a child himself touched to what a Nochri touched without intent, via something else?! This is not so difficult. Rashi says that these are the same.

Rosh (6): Rav and Shmuel must argue about Nochri children, and also about slaves after immersion, for neither can explain the Beraisa like the other. R. Chananel says that the Halachah follows Shmuel, because R. Yehoshua ben Levi holds like him, and the Halachah follows R. Yehoshua ben Levi even against R. Yochanan (and all the more so against Rav). R. Tam rules like Rav. All Gedolei Ashkenaz are lenient about what slaves touched after Tevilah, like Rav. There is no proof from R. Yehoshua ben Levi. He did not comment on Shmuel's law. He was older than him! Rather, taught that if one bought Nochri slaves and they refuse to immediately, he may keep them for 12 months. The Gemara cited this to explain Shmuel's law.

Rosh (7): R. Tam said that even if the Halachah follows Shmuel regarding buying slaves, the Halachah follows Rav regarding a child. Shmuel argues only according to the opinion that spit and Medrasan of Nochrim are Tehorim. Perhaps Shmuel did not hear the Beraisa, or he holds like the opinion that they are Tamei. Bahag rules that a baby Nochri makes Yayin Nesech. The Rashbam and Rivan say in the name of Rashi that Ge'onim say that nowadays we do not forbid Hana'ah from wine of Yisrael that Nochrim touched, for they are not used to being Menasech. They are like Nochrim ignorant of idolatry, i.e. children, so they forbid only drinking, but not Hana'ah.

Tosfos (57b DH Le'afukei): R. Tam says that the Halachah follows the opinion that spit and Medrasan of Nochrim are Tehorim, for it is a Safek about a mid'Rabanan law. Nowadays Nochrim are like children; they forbid only benefit from our wine, like Rav. We rule like Rav also regarding slaves; our custom is to permit slaves to touch wine immediately after they circumcise and immerse.

Poskim

Shulchan Aruch (YD 124:1): A Nochri child who does not mention idolatry or Meshamshim, if he touched wine he forbids only drinking it, but not benefit from it.

Beis Yosef (DH Lo): 'One day old' refers to a child who does not know well idolatry or Meshamshim. The Rashba says that knowing them well is when he remembers and mentions dolatry or Meshamshim with his mouth. A Tosefta says that an adult is one who vows (to idolatry) and mentions it and Meshamshim. R. Chananel, Bahag and the Ri rule like Shmuel. R. Tam rules like Rav; it seems that the Rosh agrees. The Ran says that the Ramban agrees, and so rule the Rashba and Rambam. We follow the Rosh and Rambam.

Prishah (1): The Tosefta means that he mentions idolatry with his mouth, and through this we know that he remembers it in his thoughts. Therefore, even if he did not say anything when he touched, since we hear him regularly mention idolatry, presumably he was thinking about it at the time he touched.

Taz (1): I say that 'with their mouths' refers to remembering and mentioning. I.e. he says it with intent. This is why the Shulchan Aruch says only 'mentions'.

Shulchan Aruch (3): If one bought slaves from a Nochri and they circumcised and immersed, immediately they are not Menasech. One may drink wine that they touched, even though they do not yet follow laws of Yisrael and they still mention the names of idolatry.

Beis Yosef (DH ha'Koneh): The Rashba says that Shmuel discusses only one who bought from Nochrim. If he bought from a Yisrael, immediately after Milah and Tevilah he is a full Yisrael, for the name of idolatry is not fluent in his mouth. R. Yonah (Igeres ha'Teshuvah 2:40) says that if a Yishmaelis immersed to become a Shifchah, but does not believe in Torah and does not fulfill the Mitzvos of women, wine that she touched is Yayin Nesech. She is like a Nochris in every way. We hold like the Rambam, Rosh, Tosfos and Rashba who permit drinking it.

Shach (6): The Ro'oh and Ra'avan hold like the Ran, that all immediately permit a slave who willingly circumcised and immersed. They must hold like Rashi, that one can immerse a slave Bal Korcho. We hold (267:5) that one cannot, so the argument must be about slaves who willingly circumcised and immersed.