Nissim ben Reuven Gerona - the Ran - ר"ן - judges and interprets the book of Rabbi Alfasi: Commentary of Rabbi Nissim or Commentary of the Ran. Lived in Barcelona in the years 1320-1380. The Rabbi was born in the small city of Girona in Spain. His first Torah teacher was his father Rabbi Reuven ben Rabbi Nissim, and he was also among his students under Rabbi Peretz Haka. The influence of Rabbi David Bonfid is evident on his writings and his style of study. which he brings many of his own opinions in his revisions to the Sanhedrin tractate and the Passover tractate, sometimes quoting entire paragraphs from his composition. He also learned from other scholars of his generation whose names have not yet been deciphered. He was on friendly terms with Ben R. Vidal de Tolosa, author of a Mishnah on Maimonides. The Rabbi made an effort to uphold the laws of the Jewish Rabbinate and save it from its perpetrators. He sometimes opposes Rashi and also Rabbeinu Tam, and against Rambam, Ramban and Rashba. However, he disagreed with our sages regarding the halachic practice. His generation, in his matriculation, was a judge and a halachic teacher in Barcelona, Spain. He taught and held a yeshiva in Barcelona. During his tenure as rabbi of the Barcelona community, Rabbi Nissim tried to prove the rich of the community on their path, this after the rich in the generations before the expulsion from Spain began to disregard the observance of mitzvot and this may have been one of the circumstances of the rebuke. The attempt to rebuke him did not succeed as the wealthy of the community refused to change their lifestyles and observe mitzvot more strictly.
The description of these things is given in the Shu'at written by his student the Rabbi (Rabbi Yitzchak bar Sheshat Barfat): "And while I was alive, I saw in Barcelona our teacher, Rabbi Nissim ztzel, when he wanted to prove some thing about himself, the rich of the community would defy him and reject his advice." (Shut Ha'Rivash, answer Tamaz). The wealthy of the Barcelona community persecuted him and reported him to the government.
Ran is considered an expert arbiter, and from all over Israel they would turn to him for halacha and to solve their questions. He also sent his answers outside his country: to Germany, France, Italy, North Africa and even to the Land of Israel. While he was serving as a rabbi in Barcelona, he and some of the dignitaries and rabbis of the community were accused of false gossip and slander, as a result of which they were banned for five months, at the end of which they were found to be innocent and released. The period of the Rabbi's activity extends from approximately 1350 CE, a year mentioned in one of his answers, until the ninth of Shevat in 1376 when he died. In one of his sermons, the Ran mentions the Black Plague as an event that occurred thirteen years earlier. The Rabbi writes "that we heard the late Ran ran away from the plague twice". His book "Sermons of the Rabbinate" is attributed to one of the fundamental books of thought in Judaism as a whole.
The Ran's books
His most important composition is his Commentary on the Rif (Alphasi), which explains its laws in detail, in clear language and in a clear manner.
The HaRaN's Innovations - חידושי הר"ן - Prior to the interpretation of the RIF, the Rabbi wrote innovations on some of the tractates of the Talmud. In this composition, he does not directly interpret the RIF - the conclusion of the issue - but extends discussions on the language of the Gemara and its interpretation. Some of these innovations have not yet seen the light of day.
Commentary to Tractate Nadarim - In this tractate, the commentary, which was printed in the Shas editions alongside the Gemara, is the main commentary for students of the tractate, since the usual commentaries, Rashi and additions to this tractate are not found in a regular edition.
Commentary on the Torah - we only have in our possession the passages from Genesis to the life of Sarah, and the beginning of the Book of Leviticus. And it seems he didn't have time to write more.