רבי דוסתאי בר' ינאי

Rabbi Dosta'i bar Rabbi Yanai [see Yalkut Melachim II 17 regarding the exile of the ten tribes, where the king sent Rabbi Dosta'i bar Rabbi Yanai and Rabbi Savi, and so it is in the Kli Yakar on the aforementioned sign]. In our study of Parashat Vayeshev [(and in Pirkei deRabbi Eliezer Chapter 38)], it is stated that Sennacherib sent to the Kutim in Samaria for Rabbi Dosta'i bar Rabbi Yanai [(and Rabbi Zechariah and Rabbi Savi)] to learn Torah.

And do not think that he is Rabbi Dosta'i bar Rabbi Yanai, a student of Rabbi Meir [(mentioned below nearby)], for there are a thousand years between them. [And it is very puzzling that the title of Rabbi began with the students of Rabbi Yochanan ben Zakkai and onward, as stated in the Aruch under the entry for Abaye. And how could Rabbi Dosta'i, Rabbi Zechariah, and Rabbi Savi, who preceded Rabbi Yochanan ben Zakkai by a thousand years, be called by the title Rabbi?]