Hoshaiah or Oshaya (Also spelled: Oshaia;Hebrew: אושעיא, הושעיה; died ca. 350 CE) was a Jewish amora of the 3rd and 4th amoraic generations. It is supposed that his colleague Hanina was his brother (Sanh. 14a; see Edels, Ḥiddushe Agadot, ad loc.). They were lineal descendants from Eli the priest, which circumstance they assigned as reason for Johanan's failure to ordain them. For a living they plied the shoemaker's trade.
Furthermore, the Talmud refers once to Hoshaiah and Ḥanina as rabbis (with the generic term Rav) in Sanh. 67b, when dealing with the laws differentiating magic as illusion and as wizardry. Hoshaiah and his colleague stand out as producing magic while studying Sefer Yetzirah, which is there considered neither illusion (aḥizat eynayim, literally "catching of the eyes") nor sorcery.
Hoshaiah and Ḥanina are also mentioned in connection with a certain bath-house, the ownership of which was contested by two persons, one of whom turned over the property as "heḳdesh" (for sacred use), causing Hoshaiah, Ḥanina, and other rabbis to leave it (B. M. 6b). On the day Hoshaiah died, it is claimed, the largest date-palm in Tiberias was uprooted and fell (Yer. Ab. Zarah iii. 42c).
A different Hoshaiah or Heshaiah is also mentioned in the Book of Jeremiah 42:1
Since the late twentieth century, a Jewish illusionist borrowed this name in being called Oshaya the Seer, obviously inspired by the famous amora and his skills in the magical arts.
Jewish Encyclopedia bibliography 
- Yuḥasin. ed. Filipowski, p. 118, London, 1857;
- Heilprin, Seder ha-Dorot, ii.36, Warsaw, 1878;
- Frankel, Mebo, p. 75, Breslau, 1870;
- Jolles, Bet Wa'ad, p. 20a, Cracow, 1884;
- Bacher, Ag. Pal. Amor. iii.565.
- This article incorporates text from a publication now in the public domain: "Hoshaiah". Jewish Encyclopedia. 1901–1906.
- supposed Twitter account of magician Oshaya the Seer.