Isaac ben Reuben Albargeloni (born 1043) was a Spanish Talmudist and liturgical poet born in Barcelona, Catalonia. He was a judge in the Denia community, where he became connected with ibn Alḥatosh, likely due to becoming his son-in-law. Among his later descendants was Moses ben Naḥman (Naḥmanides); Judah Albargeloni is said to have been Isaac's pupil. He was one of five prominent contemporaneous scholars named Isaac and the regard in which he was held by his own and succeeding generations is indicated by the fact that he is simply designated "Ha-Rab Albargeloni." He wrote commentaries on various sections of the tractate Ketubot, and at the age of thirty-five (1078) translated, from the Arabic into Hebrew, Hai Gaon's Ha-Miḳḳaḥ weha-Mimkar, on buying and selling (Venice, 1602, and frequentl