Biography
Rabbi Achi b’Rabbi Yoshiya was a tanna whose teachings appear across several tractates of the Talmud. In Bava Batra he is brought (with a variant reading naming him Rabbi Acha) on the laws of acquiring an animal by leading it, holding that it is acquired only once it walks the full length of its body.
His comments often turn on close reading of Scripture. In Gittin he addresses the case of a slave who fled, explaining a verse as speaking of a slave who escaped from outside the Land of Israel to the Land of Israel. In Sotah he holds the view that the scroll of one sotah may be used to give the bitter waters to another sotah, a position discussed and qualified by Rav Nachman bar Yitzchak, who distinguishes between a scroll already written for the purpose of a particular sotah and a Torah scroll written for the sake of learning; this same discussion is echoed in Eruvin.
Where traditions differ. Bava Batra 75b preserves a variant reading 'Rabbi Acha' alongside 'Rabbi Achi'. ; The Shabbat 79b passage names 'Rabbi Achi bar Chanina,' which may be a different sage.
רבי אחי ברבי יאשיה היה תנא בבלי בן הדור החמישי שחי בסוף המאה השנייה לספירה. מוזכר בברייתות המובאות בשני התלמודים, באבות דרבי נתן ובמדרשי ההלכה.
Ahai ben Josiah was a halakhist usually identified as a second-century Babylonian tanna. According to The Jewish Encyclopedia he is mentioned in the Babylonian Talmud but not the Jerusalem Talmud, supporting a Babylonian association. His reputation was as a teacher of strict morality: "Whoever eyes woman will eventually fall into sin and whoever watches her step will rear unworthy children"."
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