Nissim ben Reuven (1320 – 9th of Shevat, 1376, ) of Girona, Catalonia was an influential talmudist and authority on Jewish law. He was one of the last of the great Spanish medieval Talmudic scholars. He is also known by his Hebrew acronym, the RaN (), or else with the definite article HaRaN (), as well as by the name RaNbaR (), the Hebrew acronym of his full name, including his father's name, Reuven (), and also by Nissim Gerondi. Biography Nissim was born in Barcelona, Catalonia. He was a physician and had knowledge of astronomy. His teacher is not known; his works refer to a R. Perez as morenu ("our teacher"), but as he refers to his father (Reuben ben Nissim) as "my father and teacher" perhaps his father was his primary teacher. He served as a judge and teacher for the Jewish community in Barcelona, and founded a yeshiva there. He criticized the wealthy members of the community for their behavior, but this provoked a hostile backlash from them. He suffered at the hands of certain wealthy and powerful Jews of his community, who even slandered him and other leading rabbis before the government, and they were even imprisoned for a period of five months before their innocence was proven. When the Spanish Jews combined to send a petition to the king entreating his protection, Nissim was one of the committee who drafted the document. His closest students were the Isaac ben Sheshet and Hasdai Crescas. Scholarship Commentary on Alfasi His best-known work is his commentary and explanation of Isaac Alfasi's Sefer Ha-halachot, which had, at that time, been adopted for practical decisions. He is very detailed and explicit where the subject is important from a practical point of view, but extremely brief when dealing with theory. Ran did not write the commentary on all of Alfasi, although the whole commentary is often ascribed to him. In his comments he did not hesitate to refute the greatest earlier authorities, such as Rashi, Rabbenu Tam, Maimonides, Nachmanides, and Solomon ben Aderet. However, he showed his reverence for these teachers by adopting their opinions in practise. Frequently, he would refute the opinion of an earlier teacher but then write: "Yet since the ancients have decided thus, their conclusions may not be set aside." According to his student Isaac ben Sheshet, he was generally very cautious in his decisions and inclined