Ilfa said to Rabba bar Chana, "You are students of Rabbi Yochanan; we will act according to Rabbi Chanina." In what manner? A woman [(Sotah 2)].
However, the version of the Gemara is "Ipa," and Rashi explains "Ipa ben Rechava" [(see there)]. It is difficult to uphold this version because Rechava, the father of Ipa, was a student of Rav Yehuda [(see there)], and Rabba bar Chana was a student of Rabbi Yochanan, and Ilfa was a colleague of Rabbi Yochanan. Although Rabba bar Chana was also during the time of Rav Yehuda [(see there)], it seems unlikely that Rabba bar Chana was contemporaneous with Ipa ben Rechava, who was a student of Rav Yehuda.
Moreover, it is necessary to interpret that Ilfa said to Rabba bar Chana because both were in Eretz Yisrael, but Ipa and Abimi were sharp scholars from Pumbedita, and their father Rechava was from there and studied Shevuot in Rabba, who was the head in Pumbedita. It appears that Rabba bar Chana, who was during the time of Rav Yehuda, and Rabbi Yochanan went to visit him in his illness; he is the other Rabba bar Chana who was a student of Rabbi, and when he descended to Babylonia, Rabbi granted him permission to judge and permit firstborns [(see there)].
However, Rabba bar Chana, a student of Rabbi Yochanan, was not in Babylonia, and Rav Yehuda was the head in Pumbedita; therefore, Rechava was his student. In the chapter of finding the woman, Rashi explains that Ilfa was a wise man, a colleague of Rabbi Yochanan. They were poor and went to trade. Rabbi Yochanan heard that an angel wanted to punish them for abandoning the Torah, and one angel said to his colleague that for one of them, the time is established [and Ilfa did not hear; he said, "For me, the time is established"], and he returned and appointed him to Rabbi Yochanan [and he became wealthy].
And Ilfa hung himself on the railing of the ship and said, "Whoever asks me from the Mishnah of Rabbi Oshaya, and I do not clarify from the Mishnah, I will fall and drown." And he was asked by an old man, "The one who says, 'Give a shekel to my sons,' etc." (Taanit 21a). And in the Jerusalem Talmud, in the first chapter of Kiddushin, law 1, Halfi said, "I was seated on the bank of the river, and I did not take the Mishnah of Rabbi Chiya Rabba from the Mishnah; they threw me into the river" (see Halfi, for in the language of the Jerusalem Talmud, he is Ilfa).
Rabbi Yehuda bar Chiya heard Ilfa say before Rabbi Peda, Zevachim (13b). Rabbi Yochanan asked Ilfa about Zevachim (20b, Rosh HaShanah 1). And Rabbi Yochanan said in his name in Shas and there (21a). Rabbi Yirmiya in his name.
Halfi asked about the gleanings in his falling; what is the law regarding the sanctification of Peah? (Sotah 67). And it is written in the field of Yehoshua that he is Ilfa from Bavel in Temurah (25a); Ilfa asked about the gleanings in his falling.
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