(ו) אֵלּוּ דְבָרִים שֶׁל גּוֹיִם אֲסוּרִין וְאֵין אִסּוּרָן אִסּוּר הֲנָאָה... וְהַפַּת, וְהַשֶּׁמֶן שֶׁלָּהֶן. רַבִּי וּבֵית דִּינוֹ הִתִּירוּ בַשֶּׁמֶן. וּשְׁלָקוֹת
(6) These are the items of non-Jews that are prohibited, yet their prohibition is not against deriving benefit from them:.. [their] bread, and their oil [although] Rabbi and his court permitted [their] oil, and stewed vegetables,
אלא על פיתן ושמנן משום יינן ועל יינן משום בנותיהן ועל בנותיהן משום דבר אחר ועל דבר אחר משום ד"א
Rather, they issued a decree prohibiting their bread and their oil due to their wine. And they issued the decree prohibiting their wine due to the fact that this leads to familiarity, and Jews will come to marry their daughters. And they issued a decree prohibiting their daughters due to something else, idolatry. And they further issued a decree on something else due to something else
א"ר אסי א"ר יוחנן משום ר' יהודה בן בתירא שלשה יינות הן יין נסך אסור בהנאה ...סתם יינם אסור בהנאה .... המפקיד יינו אצל עובד כוכבים אסור בשתיה ומותר בהנאה
Rabbi Asi says that Rabbi Yoḥanan says in the name of Rabbi Yehuda ben Beteira: There are three kinds of prohibited wines: It is prohibited to derive benefit from wine used for a libation.. It is prohibited to derive benefit from nondescript wine of a gentile...With regard to the wine of one who deposits his wine with a gentile, one is prohibited from drinking it, but one is permitted to derive benefit from it.
אתמר מפני מה אסרו שכר של עובדי כוכבים רמי בר חמא אמר רבי יצחק משום חתנות רב נחמן אמר משום גילוי...
רב פפא מפיקין ליה לאבבא דחנותא ושתי
רב אחאי מייתו ליה לביתיה ושתי
ותרוייהו משום חתנות רב אחאי עביד הרחקה יתירתא
It was stated: Why did the Sages prohibit the beer of gentiles? Rami bar Ḥama says that Rabbi Yitzḥak says: For fear that they will marry them.
Rav Naḥman said: Out of fear of exposure...
Rav Pappa had them bring out the beer belonging to gentiles from the store to the entrance of the store, and he would drink it there.
Rav Aḥai had them bring the beer to his house, and he would drink it there.
And both of them did so out of concern for marriage with gentiles. Rav Aḥai established an extreme preventive measure for himself beyond what is required by halakha.
אין דכי אתא רב דימי אמר פעם אחת יצא רבי לשדה והביא עובד כוכבים לפניו פת פורני מאפה סאה
אמר רבי כמה נאה פת זו מה ראו חכמים לאוסרה מה ראו חכמים משום חתנות אלא מה ראו חכמים לאוסרה בשדה ..
איבו הוה מנכית ואכיל פת אבי מצרי אמר להו רבא ואיתימא רב נחמן בר יצחק לא תשתעו בהדיה דאיבו דקאכיל לחמא דארמאי:
When Rav Dimi came from Eretz Yisrael to Babylonia, he said: Once Rabbi Yehuda HaNasi went out to the field, and a gentile brought before him a se’a of bread baked in a large baker’s oven [purnei]. Rabbi Yehuda HaNasi said: How exquisite is this loaf of bread! What did the Sages see to prohibit it? The Gemara asks: What did the Sages see! It was prohibited due to the concern that it would lead to marriage. Rather, he asked: What did the Sages see that caused them to prohibit bread even in the field?...
Aivu would bite and eat bread of gentiles at the boundaries of the fields. Rava said to the students in the study hall, and some say that it was Rav Naḥman bar Yitzḥak who said to them: Do not speak with Aivu, as he eats bread of Arameans.
גופא אמר רבה בר בר חנה א"ר יוחנן האי עובד כוכבים דחריך רישא שרי למיכל מיניה אפילו מריש אוניה
אמר רבינא הלכך האי עובד כוכבים דשדא סיכתא לאתונא וקבר בה ישראל קרא מעיקרא שפיר דמי פשיטא מהו דתימא לבשולי מנא קא מיכוין קמ"ל לשרורי מנא קא מיכוין אמר רב יהודה אמר שמואל הניח ישראל בשר על גבי גחלים ובא עובד כוכבים והפך בו מותר
Rabba bar bar Ḥana says that Rabbi Yoḥanan says: The gentile who singed the head of an animal, it is permitted to eat part of it, even from the tip of the ear, which is fully cooked.
Ravina said: Therefore, this gentile who threw a moist peg into the oven, and a Jew had already inserted a gourd in the oven from the outset, the gourd is permitted, even though it was in effect cooked by a gentile.
Isn’t that obvious? What might you have said? That the gentile intends to cook the vessel, i.e., the peg, by softening it. Therefore Ravina teaches us that he intends only to harden the vessel.
Rav Yehuda says that Shmuel says: If a Jew placed meat upon flaming coals and a gentile came and turned the meat over, the meat is permitted....
רבה ורב יוסף דאמרי תרוייהו יין מזוג אין בו משום גילוי יין מבושל אין בו משום ניסוך
Rabba and Rav Yosef both say: Diluted wine is not subject to the halakha of exposure, according to which the consumption of a liquid is prohibited if it is left uncovered; and cooked wine is not subject to the halakha of libation.
Shmuel and Ablet, a gentile scholar, were sitting together, and others brought cooked wine before them. Ablet withdrew his hand to avoid rendering the wine prohibited to Shmuel. Seeing this, Shmuel said to Ablet that the Sages said: Cooked wine is not subject to the prohibition of wine used for a libation, and therefore you need not withdraw your hand on my account.
אמר רב משרשיא מה טעם הואיל ופשט איסורו ברוב ישראל שמן לא פשט איסורו ברוב ישראל דאמר רבי שמואל בר אבא אמר רבי יוחנן ישבו רבותינו ובדקו על שמן שלא פשט איסורו ברוב ישראל וסמכו רבותינו על דברי רשב"ג ועל דברי רבי אלעזר בר צדוק שהיו אומרים אין גוזרין גזירה על הצבור אא"כ רוב צבור יכולין לעמוד בה
Rav Mesharshiyya said: What is the reason that none of the eighteen decrees can be voided? Since the prohibition spread among the majority of the Jewish people, it cannot be voided. But with regard to oil, its prohibition did not spread among the majority of the Jewish people, and therefore it can be voided. As Rabbi Shmuel bar Abba says that Rabbi Yoḥanan says: Our Sages sat and inspected the matter of gentiles’ oil and determined that its prohibition had not spread among the majority of the Jewish people, and our Sages relied upon the statement of Rabban Shimon ben Gamliel and upon the statement of Rabbi Elazar bar Tzadok, who would say: The Sages issue a decree upon the community only if most of the community is able to abide by it.
From Haym Soloveitchik, Wine in Ashkenaz in the Middle Ages, p. 315 (my translation)
In the Hellenistic world around the Mediterranean basin, where vines grow plentifuly, beer was considered a second-rate beverage and was not the basis of companionship. Babylonia, on the other hand, is not wine country, and beer there was always "the wine of the region." Thus only in Babylonia and only in the Bavli do we hear of a decree against beer. Since Europe was first settled by Jewish immigrants from the Roman Empire, they did not even know of a prohibition of beer. When the Bavli became accepted there as the source of authority, it is doubtful whether the community knew of this prohibition, which is mentioned, after all, on only a few lines of the Bavli, in Tractate Avodah Zarah, a tractate not learned in Ashkenaz. There is no doubt that over the generations this prohibition became known, but since in the regions of the Rhine, Champagne and Paris they did not drink much beer, knowing the prohibition had little effect. Thus, unlike the prohibition of wine, the prohibition of beer was not deeply entrenched in the self-identity of Ashkenazi Jews. Yayin nesekh was also related to the long-lasting struggle against paganism, a struggle which left an unerasable mark on both halakhah and popular sentiment. The loathing of idolatry and anything connected to it penetrated deeply into the people's spirit, and even in "the land of Edom" where idolaters did not libate their wine, the abhorrence of drinking Gentile wine did not dissipate. Beer had no similar background, and therefore did not arouse any associations, or loathing that such associations could engender. The prohibition is abstract and marginal in the laws of Avodah Zarah, and was thought of in this way in the academies of the Tosafot.