Biography
Rav Tzemach Gaon was one of the Geonim, the heads of the Babylonian academies whose responsa and rulings shaped halachah for generations after him. He appears in the writings of later authorities as a voice on questions of practical law, his answers being preserved and brought down by the Rishonim who followed.
His rulings touch a range of subjects. In matters of monetary law he is cited regarding the collection of fines and damages in Babylonia, drawing the distinction that fines and injuries are not collected there, while compensation for healing and lost work is. Rav Alfas brings a ruling in his name (Choshen Mishpat 285) distinguishing between land and money belonging to a minor when relatives are involved. He is also drawn upon in the laws of chalitzah and the requirement of three valid judges (Even HaEzer 169), as well as in matters concerning circumcision and its blessings (Yoreh De’ah 265) and the order of the Kiddush on Sukkot (Orach Chaim 643). Across these passages he is preserved as an early halachic authority whose words the codifiers weighed and cited.
Where traditions differ. Some passages quote rulings attributed to other Geonim alongside or near Rav Tzemach; the specific attribution to him should be checked against the source where the passages overlap.
רב צמח בן פלטוי גאון היה גאון ישיבת פומבדיתא לקראת סוף תקופת הגאונים, במשך תשע עשרה שנה, בשנים ד'תרל"ב-ד'תר"ן (872–890).
Smah bar Paltoy, also known as Tzemach ben Poltoi and Zemaḥ Gaon, was the gaon "president" of Pumbedita Academy in Lower Mesopotamia from 872 up until his death in 890. He is an important figure in the history of Rabbinic Judaism.
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