The Mishneh Torah (Hebrew: מִשְׁנֶה תּוֹרָה, "Repetition of the Torah") subtitled Sefer Yad HaHazaka (ספר יד החזקה "Book of the Strong Hand,") is a code of Jewish religious law (Halakha) authored by Maimonides (Rabbi Moshe ben Maimon, also known as RaMBaM or "Rambam"), one of history's foremost rabbis. The Mishneh Torah was compiled between 1170 and 1180 (4930-4940), while Maimonides was living in Egypt, and is regarded as Maimonides' magnum opus. Accordingly, later sources simply refer to the work as "Maimon", "Maimonides" or "RaMBaM", although Maimonides composed other works.
Mishneh Torah consists of fourteen books, subdivided into sections, chapters, and paragraphs. It is the only Medieval-era work that details all of Jewish observance, including those laws that are only applicable when the Holy Temple is in existence, and remains an important work in Judaism.
Its title is an appellation originally used for the Biblical book of Deuteronomy, and its subtitle, "Book of the Strong Hand," derives from its subdivision into fourteen books: the numerical value fourteen, when represented as the Hebrew letters Yod (10) Dalet (4), forms the word yad ("hand").
Maimonides intended to provide a complete statement of the Oral Law, so that a person who mastered first the Written Torah and then the Mishneh Torah would be in no need of any other book. Contemporary reaction was mixed, with strong and immediate opposition focusing on the absence of sources and the belief that the work appeared to be intended to supersede study of the Talmud. Maimonides responded to these criticisms, and the Mishneh Torah endures as an influential work in Jewish religious thought. According to several authorities, a decision may not be rendered in opposition to a view of Maimonides, even where he apparently militated against the sense of a Talmudic passage, for in such cases the presumption was that the words of the Talmud were incorrectly interpreted. Likewise: "One must follow Maimonides even when the latter opposed his teachers, since he surely knew their views, and if he decided against them he must have disapproved their interpretation."
Read more about Mishneh Torah: Origin, Sources, and Language, Language and Style, The Books and Sections, Printed Editions and Textual Accuracy, English Translations