Rabbi Nathan ben Jehiel of Rome רבי נתן בן יחיאל מרומי

Rome in his day was a community without a first rank yeshiva but with a long memory: the Anav family counted its scholars back over centuries. His father, Rabbi Jehiel ben Abraham, was both a teacher of law and a liturgical poet, of whom Italy then had many. Rabbi Nathan himself studied in several lands: under Rabbi Mazliah ben Eliyahu in Sicily, who had heard Rav Hai Gaon, the last gaon of Pumbedita; under Rabbi Moshe HaDarshan in Narbonne; and in the yeshivot of Pavia and Bari.

Out of those roads came the Arukh. The Talmud is written in several dialects of Aramaic and holds words brought in by trade and by rule: Greek, Latin, Persian, Arabic, even Slavonic. A thousand years later half of them are dark to the reader. Rabbi Nathan set such words out in the order of the letters, explained each one and propped the explanation on the passage it came from. The work was finished in February, and the sources name 1101 and 1102; the difference of a year stands to this day.

The book spread quickly and was among the first to be printed: a first edition appeared around 1477 and the edition of Daniel Bomberg in 1531. Every later lexicon of the Talmud grew out of it, and at the end of the nineteenth century Alexander Kohut brought out the Arukh HaShalem, the same lexicon with the additions of eight centuries of scholars.