When wine is left where a non-Jew can easily come into contact with it, must we be concerned that he may have touched the wine?
The Mishnah on today’s daf (=page) makes it clear that we do not automatically assume that a non-Jew would touch the wine. In fact, according to the Mishnah, if a Jew prepared wine and it remained in the non-Jew’s property, as long as there are Jews in the city and the wine is readily visible to the public, there is no concern at all. Even if there were no Jews in the city, a Jewish guard who was yotzeh ve-nikhnas – who passed by occasionally to check things – would be sufficient.
The Gemara relates a story where a non-Jew was found between the barrels in a place that contained kosher wine, and Rava ruled that if he would be treated like a thief were he to be found, we do not need to be concerned about the wine; we assume that he would be afraid to touch it or take anything. If, however, he would not be treated like a thief, then there is reason to worry.
Rashi explains that the idea of being treated like a thief depends on the person; if he is someone who is weak and afraid of being accused and taken before the court, we can assume that he didn’t touch the wine. According to the Ritva, we do not need to know that he will be brought up on criminal charges as a thief; even if he will be embarrassed by having been caught in a situation where he is viewed as a thief it will be enough for us to assume that he will not be touching the wine. The Ra’avad quotes the Ge’onim as explaining that this is a case where there were barrels of wine belonging to Jews in one area and to non-Jews in another area. Being treated like a thief means being caught on the wrong side of the partition and being suspected of thievery.