Avodah Zarah

R. Kahana said: We learn from the words of them all  that when [the forbidden element] imparts a worsened flavour it is permitted. Abaye said to him: As regards all the rest of them very well, but since R. Simeon b. Lakish has the words, 'When [the Rabbis] use the phrase,' it follows that he personally does not hold that view. Are we, then, to infer that there are some who maintain that when [the forbidden element] imparts a worsened flavour it is prohibited? — Yes, for it has been taught: Whether it imparts a worsened or improved flavour it is prohibited — such is the statement of R. Meir; R. Simeon says: If improved it is prohibited but if worsened it is permitted. What is R. Meir's reason? — He derives it from the vessels of Gentiles. The vessels of Gentiles, do they not impart a worsened flavour [to the food cooked in them]? and yet the All-merciful forbade them;  so here also it makes no difference [and it is prohibited]. How does the other [viz., R. Simeon establish his view]? — In the same manner as R. Huna the son of R. Hiyya who said: The Torah only forbade a utensil which had been used [by a Gentile] the same day, the effect of which is not to worsen the flavour. [What reply is made to this by] the other? — Even in the case of a pot used [by a Gentile] the same day it is impossible that it should not worsen [the flavour] a little. And what is R. Simeon's reason? — Because it has been taught: Ye shall not eat of anything that dieth of itself [nebelah]; thou mayest give it unto the stranger that is within thy gates  — whatever is fit for use by a stranger is called nebelah,