King Shapur I Performs a Jewish Practice

[With regard to] the knife, one must polish it and it is [rendered] pure. R. Ukva bar Ḥama says: And one must thrust it ten times into the ground. R. Huna ben R. Joshua says: And [this must be done] in untilled earth [i.e., hard earth]. R. Kahana says: And [this applies] to a good knife that does not have notches, [so that the entire surface of the knife is scraped against the ground]. This is also taught [in a baraita: With regard to] a good knife that does not have notches [i.e., serrated—Ed.], one can thrust it ten times into the ground. R. Huna ben R. Joshua says: [This is sufficient] for [the purpose of] eating cold [food] with it. [This is] like that [incident] involving Mar Judah, [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 Judah. 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 Judah, that he is meticulous about halakhah;] but I am not certain of [that] master, [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.”