Biography
Rabbi Yonatan ben Yosef was a Sage whose teachings are brought in baraitot throughout the Talmud, where he derives halachot from the verses of the Torah. He is cited in tractates including Chullin, Sotah, Yoma, Rosh Hashanah, and Berachot, and his rulings are taken up by later Sages — in Chullin, Rabbi Yochanan is recorded explaining a teaching in accordance with Rabbi Yonatan ben Yosef’s view.
His teachings span a range of areas. In Chullin he addresses the obligation to cover the blood after slaughtering a wild animal and then a domesticated animal, and he expounds the word “and it shall be washed” (Vayikra 13) regarding the laundering of a garment afflicted with tzaraat, teaching that the second washing is likened to the first. In Yoma he expounds “for it is holy to you” (Shemot 31), teaching that the Shabbat is given over into your hands, and you are not given over into its hands. In Rosh Hashanah he derives a point from “and it shall yield produce for the three years” (Vayikra 25). In Berachot he rules on what a mourner may study, permitting one to arrange the Mishnah but not the Gemara.
He also appears among the Sages defining who is an am ha’aretz: where Rabbi Meir, Ben Azzai, and others give their views, Rabbi Yonatan ben Yosef says it is one who has children and does not raise them to learn Torah.
Where traditions differ. The supplied era label "Acharonim" does not fit the cited material, in which this Sage is quoted in baraitot and appears alongside tannaim such as Rabbi Meir and Ben Azzai.
Jonathan ben Joseph was a Lithuanian rabbi and astronomer who lived in Risenoi, Grodno, in the late 17th century and early 18th century. Jonathan studied astronomy and mathematics.
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