Rav Huna, the Exilarch of Babylon during the time of Rabbi, was from the seed of Judah, the kings from Yehoiachin (and from Zerubbabel [as attributed in Seder HaDoros to Shemaiah and Abtalion]) on the male side, and Rabbi [(who descended from Hillel)] was from the maternal side of Judah. [And in Bereishit Rabbah, chapter 53] Rabbi said, "If Rav Huna the Exilarch would ascend here, I would establish for him above that he is from Judah, and I am from Benjamin, who is from Dovrayah, and I am from a lineage [(as mentioned regarding Hillel the Elder and Rabbi Yochanan the Nasi)]. And in the genealogies in the name of Rosh Gadol] during the days of Rabbi, Rav Huna the Exilarch was in Babylon, which is why we say [(Horayot 11)] Rabbi asked from Rabbi Chiya, "What am I like?" He said to him, "Your co-wife is in Babylon," and who is that?
Rav Huna [(in the Gemara, the words "and who is that? Rav Huna" are absent)] and those from Babylon are preferred as they are called a tribe. He died during the lifetime of Rabbi in Babylon and was buried in Eretz Yisrael, [and in the Jerusalem Talmud, chapter 9 of Kilayim, it is stated that they buried him next to Rabbi Chiya, and see above regarding Rosh Hashanah in B'laah, and it requires investigation (and see there for more).] Once, Rabbi Chiya Rabbah entered before Rabbi and said, "This is Rav Huna," and the face of Rabbi became darkened.
He said, "His coffin is coming." [And in the Chain of Tradition (page 32), in the days of Rav (it should be Rabbi), Rav Huna was from the seed of David on the paternal side, etc., and he died at the age of 70.
However, the generations of the world wrote that Rabbi Huna in B'laah died at the age of 70 (see above regarding Rosh Hashanah), and Rav Huna the Exilarch died during the lifetime of Rabbi as mentioned above, and Rabbi died before the completion of 4000 years, and thus the calendar was confused in his understanding. In Rabbah Ruth, chapter "Where you die, I will die," Rosh Hashanah the Exilarch asked Rabbi Chisdai what is the law regarding the verse "Remove the turban and lift the crown," he said, etc.
He said, "You are Chisdai, and your name is Chisdain." Therefore, it appears from this that Rosh Hashanah in B'laah, that Rav Chisdai was his student, is also called the Exilarch.
However, see in Gittin there, and it states, "The Exilarch said to Rosh Hashanah, 'From where do you know that it is forbidden?' He said, 'From the Rabbis, as we learned in the polemic, etc.' While he was saying this, Rosh Hashanah stood up to respond, and Rabbi Chiya said to Rabbi Gamliel, 'A verse is written.'" And see in the Jerusalem Talmud at the end of Sotah, the Exilarch sent to Rabbi Chiya, "What is the law regarding the verse 'Remove,' etc.?" He said, "The turban was removed, the crown was lifted." Rabbi Yochanan heard and said, "He is Chisdai, and his name is Chisdai." Thus, it is found that according to the version of the Gemara and the Jerusalem Talmud, they did not call Rosh Hashanah in B'laah the Exilarch, and the text of the Midrash Ruth is mistaken. And it requires investigation in Rashi, Makkot.
See Rabbah regarding Rabbi Huna.] And after Rosh Hashanah, the first one mentioned in Babylon was Mar Ukva [(as attributed in the name of Rosh Gadol)].
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