The Tractate of Avodah Zarah ends with a fascinating story:
“….that incident involving Mar Yehuda, an important personage of the house of the Exilarch, and Bati bar Tuvi, a wealthy man, who were sitting before King Shapur, the king of Persia. The king’s servants brought an etrog before them. The king cut a slice and ate it, and then he cut a slice and gave it to Bati bar Tuvi. He then stuck the knife ten times in the ground, cut a slice, and gave it to Mar Yehuda. Bati bar Tuvi said to him: And is that man,referring to himself, not Jewish? King Shapur said to him: I am certain of that master, Mar Yehuda, that he is meticulous about halakha; but I am not certain of that master, referring to Bati bar Tuvi, that he is meticulous in this regard. There are those who say that King Shapur said to him: Remember what you did last night. The Persian practice was to present a woman to each guest, with whom he would engage in intercourse. Mar Yehuda did not accept the woman who was sent to him, but Bati bar Tuvi did, and therefore he was not assumed to be meticulous with regard to eating kosher food.”
A non-Jewish king, Shapur, is serving an etrog to two Jews, one who is pious, and one who is not. King Shapur "sharply" distinguishes between the two, and only meticulously koshers the knife before serving one, and not the other. He explains he knows which Jew has acted according to Jewish values, and which has not.
The symbolism of this story is powerful. First of all, the etrog is a biblical symbol of beauty, yet within this etrog are divisions, and not all of the etrog is the same. The lesson is that even a people of goodness will not be uniformly good, they are not one undivided “etrog” so to speak. If Judaism aspires to bring a vision of morality and spiritual beauty to the world, a Jew must make himself worthy of this status. It is not automatically bestowed by birth.
Most importantly, like in many other tractates, the final passage Avodah Zarah comments on the theme of the tractate; in this case the message is subversive in the best sense of the word, an attempt in a few lines to balance the message of the tractate. So after an entire tractate of judging the practices of non-Jews, distinguishing between what is idolatrous and what is not, the tables are turned: now it is the non-Jewish King who is judging the Jews.
This final passage sends off the tractate with lessons that balance an otherwise endless critique of non-Jewish paganism. It reminds us that Jews are only considered worthy if they embrace Jewish values, and it cautions us not to descend into stereotypes, to recognize there are both wise and discerning non-Jewish Kings, and Jewish rascals. Even when critiquing the vapidity and corruption of surrounding cultures, don’t be intolerant; and of course, you must never become triumphalistic, forgetting that how to engage in self criticism.
Hadran Alach Mesechet Avodah Zarah.