Igros Moshe (Hebrew:אגרות משה,lit. 'Epistles of Moses';Israeli/Sephardic pronunciation:Igrot Moshe) is a nine-volume series ofhalakhicresponsa by RabbiMoshe Feinstein. The first seven volumes were published during Rabbi Feinstein's lifetime, while the remaining two were published posthumously in Jerusalem.

RabbiMoshe Feinstein was recognized during his lifetime as theposek hador, the final decisor inhalakhic queries, by much of the world's Orthodox Jewish community, due to his reputation as atalmid chacham with profound knowledge in all areas ofTorah. The most difficult questions were often mailed to him. In 1959, a compilation of these questions related to the laws ofOrach Chaim were printed in the first volume ofIgros Moshe.^[1] Later volumes were printed over the next twenty five years, with the publishing of the sixth volume in c. 1985.^[2] The remaining two volumes were published posthumously, largely based on manuscripts, with the final printing in 2011.^[3] Altogether, the series includes thousands of responsa.^[1] In addition, anindex titledYad Moshe was published, listing different ideas and where one can find relatinghalakhos in theIgros Moshe. His son-in-law, RabbiDavid Tendler, translated some ofIgros Moshe in a work titledResponsa of Rav Moshe Feinstein: translation and commentary.^[4]

On Israeli Prime MinisterMenachem Begin's trip to the United States in 1977, he visited Rabbi Feinstein in his apartment in New York. Also present at the meeting were RabbisYitzchak Hutner andYaakov Kamenetsky, also senior Haredi rabbis in the United States. Prior to Begin's arrival at the meeting, his security agents combed Rabbi Feinstein's apartment, searching for weapons or explosives that may have been planted there to harm the prime minister. Upon seeing this, Rabbi Hutner wittily remarked that if they were searching for explosives, they would "only find them in the writings of our host!" He was referring to the creative and novel ideas and decisions (chidushim) - which are sometimes referred to as bombs - that Rabbi Feinstein had penned inIgros Moshe.^[5][6]

On the tenthyahrtzeit (anniversary of death) of Rabbi Feinstein, themashgiach ruchani ofMesivtha Tifereth Jerusalem, Rabbi Chaim Ganzweig,^[7] wrote the following inThe Jewish Observer:^[6]

Every halachic decision of theRosh Yeshiva [Rabbi Feinstein],^[8] regardless of how seemingly simple or instantly rendered, was deeply rooted insugyos haShas (the discussions recorded in theTalmud). There was no superficiality in his decisions. They were based on a deep awareness and understanding of all relevant Talmudic discussions and their ramifications. He did not rely on "this opinion" or "that decision," nor did he automatically follow precedent; rather, the decision was the result of toil in, and depth of understanding of, the relevant Talmudic discussions at the source, following through the classic codes and the views of the greatposkim.

A certain individual wrote a work with the intention of refutingIgros Moshe. In the book, he listed his arguments on Rabbi Feinstein and even did so an insulting matter. To have his work published, he brought his manuscript to the same print shop that theIgros Moshe had been printed in. Although the printer, who was Jewish and an admirer of Rabbi Feinstein, did not want to print it, the rabbi instructed him to do so, telling him that printing is his form of income and that he was doing achesed (kindness) to the writer by helping him achieve his goals.^[6][9]

• Biography of HaRav Moshe Feinstein zatsal
• List of rulings by Moshe Feinstein
• Care of the Critically Ill

• Articles containing Hebrew-language text
• Sifrei Kodesh
• Rabbinic legal texts and responsa
• Hebrew-language religious books
• Moshe Feinstein
• Hebrew words and phrases in Jewish law