רבי שמעון בר כרסנא

Rav Shimon bar Karsena was an amora of Eretz Yisrael in the fifth generation, mentioned in the Talmud Yerushalmi alone; in a number of places his name appears there as Rav Shimon bar Barsena. He brings many teachings in the name of his rebbe, Rav Acha. Among them: that of all the measures none is clearer than the techum of twelve mil, the length of the camp of Israel in the wilderness — so that although techum Shabbat itself is rabbinic, going out beyond twelve mil is d’oraita; and that the sea of copper which Shlomo HaMelech made in the Beit HaMikdash served as a place of tevilah for the kohanim.

In the Yerushalmi, Rav Elazar brings teachings in his name, and it appears that Rav Elazar was his talmid; that Rav Elazar is identified either as Rav Elazar b’Rabbi Yosi or as Rav Elazar Deroma. As to where he lived, the Aruch writes that Karsena, or Barsena, was the name of the town where he made his home; others hold that Karsena was his father’s name and that he lived in Yafo.