Bava Batra

where it has been taught: If one tested  a [wine] jug for the purpose of taking from it, periodically, heave-offering [for wine kept in other jugs];  and, subsequently,  it was found [to contain] vinegar,  all  three days It is certain, [and] after that it is doubtful.  What does this mean? — R. Johanan said, It means this: During the first three days [after the test, it is regarded as] certain wine;  after that, [as] doubtful.  What is the reason? — [Because] wine [begins to] deteriorate from above,  and this [man] had tasted it [and ascertained that] it had not deteriorated; [and] if it be assumed that it had deteriorated [immediately] after it had been tasted, [even then during the first three days], it had the odour of vinegar and the taste of wine, and whenever the odour is of vinegar and the taste is of wine, it is regarded as wine. And R. Joshua b. Levi said: [The meaning of the Baraitha is that] during the last three days  [it is regarded as] certainly vinegar;  prior to that, [as] doubtful.  What is the reason? — Wine [begins to] deteriorate from below, and it is possible [that it had already] deteriorated [during the test] but he did not know.  [Moreover, even] if it is assumed that deterioration [begins] from the top, [and it will be argued that it must have been wine] since [this man] had tasted it and [ascertained that] it had not [then] deteriorated, [it may be retorted that] it is possible that it deteriorated [immediately] after he tasted it, [and it had] the odour of vinegar and the taste of wine, and [the law is that wherever] the odour is vinegar and the taste. wine, [it is regarded as] vinegar. The scholars of the South [of Palestine] taught in the name of R. Joshua b. Levi: [During the] first [three days it is regarded as] certainly wine.  [During the] last [three days, as] certainly vinegar. [During the] intervening [days as] doubtful. Is not this self-contradictory? [Since] you said that [during the] first [three days it is regarded as] certainly wine, it is obvious that [if the] odour is vinegar and the taste wine, [it is regarded as] wine;  and then you say [that during the] last [three days it is regarded as] certainly vinegar, [which] proves clearly [that if the] odour is vinegar and the taste, wine, [it is regarded as] vinegar?  — [The second clause deals with the case] when it was found [to be] very strong vinegar [in which case it is known] that had it not lost its taste three days [previously], it could not have been found [to be such] very strong vinegar. According to whom  did [R. Joseph] answer him?  — R. Mari and R. Zebid [are in dispute on this]. One says: According to R. Johanan. and the other says: According to R. Joshua b. Levi. It has been stated: [In the case] when one sold a jug of wine to another and it became sour,  Rab said: During the first three days [of the sale] it is [regarded as still] in the possession of the seller;  after that, [it is regarded as] in the possession of the buyer.