Avodah Zarah 58B

מימר אמר: סלקא דעתיה דרבנן כי הני שיכרא קא שתו? אלא ודאי האי חמרא הוא, ונסכיה. מאן דשרי שפיר שרי, מימר אמר: סלקא דעתך דרבנן כי הני חמרא קא שתו, ואמרו ליה לדידי ״תא אשקינן״? אלא ודאי שיכרא הוא (קא שתו), ולא נסכיה.

the non-Jew says to himself: Can it enter your mind that great rabbis like these are drinking liquor [shikhra]? Rather, this is certainly wine that they are drinking, and therefore the non-Jew may have poured it as a libation. R' Yehoshua ben Levi continues to explain that the one who deemed the wine permitted properly deemed it permitted, as he holds that the non-Jew says to himself: Can it enter your mind that great Rabbis like these are drinking wine and they say to me, a non-Jew: Come, serve us drinks? Rather, it is certainly liquor that they are drinking, and therefore he did not pour it as a libation.

והא קא חזי! בליליא. והא קא מרח ליה! בחדתא.

The Talmud asks: But doesn’t the non-Jew see whether it is wine or liquor? The Talmud answers: The incident occurred at night. The Talmud asks: But doesn’t the non-Jew smell it and recognize that it is wine? The Talmud answers: This incident occurred with new wine, whose smell does not diffuse.

והא קא נגע ביה בנטלא, והוה ליה מגע גוי שלא בכוונה ואסור! לא צריכא, דקא מוריק אורוקי, והוה ליה כחו שלא בכוונה, וכל כחו שלא בכוונה לא גזרו ביה רבנן.

The Talmud asks: But didn’t the non-Jew touch the wine when he drew the wine in the pail, and therefore it is a case of a non-Jew’s unintentional touch, which renders the wine prohibited? The Talmud replies: No, it was necessary to teach this halakha because the non-Jew was pouring from one vessel to another without touching the wine, and therefore it was a case where the wine was poured by the force of the non-Jew’s action, without any intention of offering it as a libation. And in any case where wine is poured by force of a non-Jew’s action, without any intention of offering it as a libation, the rabbis did not issue a decree prohibiting the wine, and it is permitted to drink it.