Rabbi Oshaya and Rabbi Yehuda Nasi were the students of Rabbi Yehuda [(Baba Kamma (19b) the text of Rabbi Yehuda is a mistake and should be Rabbi Yehuda)]. And perhaps this is Rabbi Oshaya [(Rabba)] who lived many years [(i.e., until the days of Rabbi Yehuda)].
However, in the chapter of the entrusted [(Mishnah 43b)], Rabbi Oshaya said to Rabbi Yehuda, "Rabbi, you say thus" [(so said Rabbi Asi in the name of Rabbi Yochanan)], it seems that this is not Rabbi Oshaya Rabba. And in the chapter of all the divorce documents [(25a)], Rabbi Yehuda asked and Rabbi Oshaya said to him, "My son, what is the connection to Pesachim?" [(In the chapter of the one who injures (Perek 8, Mishnah 2), Rabbi Abba said it before Rabbi Oshaya, and Rabbi Oshaya said it before Rabbi Yehuda, and he said thus said Shmuel)].
And in the Tosafot on Yevamot [(19a)], Rabbi Oshaya at the end of 19 [(37, and page 10)] is not Rabbi Oshaya of the chapter of the one who dwells [(and they wrote Rabbi Oshaya separately and Rabbi Oshaya separately, and we find Rabbi Oshaya who was in the days of the later Amoraim who asked from Rabbi Yehuda, and thus wrote the Tosafot in the chapter of the one who dwells, Sicha 8)].
Furthermore, how was he in Babylon, and it is also difficult who appointed Rabbi Yehuda Nasi in Babylon as the student of Rabbi Yehuda, and perhaps he went there once or Rabbi Yehuda went to Eretz Yisrael [(see Rachba)]. And in the first chapter of Megillah [(7, Mishnah 1)], Rabbi Yehuda Nasi sent to Rabbi Oshaya. And in the Jerusalem Talmud Megillah, chapter 1, halacha 6, Rabbi Yudan Nasi sent to Rabbi Oshaya Rabba, etc., "The calf that was sent to you, Rabbi Oshaya, remains with us, our Rabbi, etc." It seems that Rabbi Oshaya was a student of Rabbi Yehuda Nasi.
And it is difficult in my eyes to say that Rabbi Oshaya Rabba was a student of Rabbi Yehuda Nasi for several reasons.
Furthermore, in the Jerusalem Talmud, in the first chapter of Beitzah, halacha 11, Rabbi Oshaya Rabba said to Rabbi Yehuda Nasi, "Did you hear from your father that a chicken is permitted to be moved?" He said to him in a whisper. He said to him, "Why did you say to me in a whisper?" He said to him, "Just as I heard in a whisper, so I say to you in a whisper." And if his teacher had heard from either Rabbi or from your father, why did he not say, "Rabbi told me in a whisper?" And we find in Baba Kamma that Rabbi Yehuda Nasi was alive when Rabbi Yehuda died, as mentioned in the first chapter.
And in my opinion, necessity will not be condemned, for there were two Rabbi Yehuda Nasi [(as explained above)] and two Rabbi Oshaya as mentioned.
Therefore, the second Rabbi Oshaya and the second Rabbi Yehuda Nasi were the students of Rabbi Yehuda, and the second Rabbi Oshaya called the second Rabbi Yehuda Nasi "Rabbi," and Rabbi Oshaya Rabba said to the first Rabbi Yehuda Nasi, "Did you hear from your father?" for he was not his teacher. And the second Rabbi Yehuda Nasi was alive when Rabbi Yehuda died. And according to this, you will understand many complexities in the Talmud.
And it is possible that it is necessary to say that the Tosafot differentiate between Rabbi Oshaya and Rabbi Oshaya Rabba, for according to the order of the generations, you will find that there were two Rabbi Oshaya, thus it seems to me. But according to what is stated in the Jerusalem Talmud of Megillah mentioned above, that Rabbi Yudan Nasi sent to Rabbi Oshaya Rabba, therefore it cannot be explained thus.
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