His commentary, the Beit HaBechirah, is one of the most monumental works written on the Talmud. This work is less a commentary and more of a digest of all of the comments in the Talmud, arranged in a manner similar to the Talmud—presenting first the mishnah and then laying out the discussions that are raised concerning it. Haym Soloveitchik describes it as follows: Unlike most rishonim, he frequently quotes the Jerusalem Talmud, including textual variants which are no longer extant in other sources. Beit HaBechirah cites many of the major Rishonim, referring to them not by name but rather by distinguished titles. Specifically:
A complete copy of Beit HaBechira was preserved in the Biblioteca Palatina in Parma, rediscovered in 1920, and subsequently published. Much of Beit HaBechirah was published long before the publication of the Parma manuscripts. Nevertheless, the common perception has been that the Meiri's works were not available to generations of halachists before 1920; early 20th century authors such as Chafetz Chaim, Chazon Ish, and Joseph B. Soloveitchik write under the assumption that Beit HaBechira was newly discovered in their time. Beit HaBechira has had much less influence on subsequent halachic development than would have been expected given its stature. Several reasons have been given for this. Some modern poskim refuse to take its arguments into consideration, on the grounds that a work so long unknown has ceased to be part of the process of halachic development. One source held that the work was ignored due to its unusual length. Professor Haym Soloveitchik, though, suggested that the work was ignored due to its having the character of a secondary source - a genre which, he argues, was not appreciated among Torah learners until the late 20th century.
Other works
Menachem Meiri is also noted for having penned a famous work used to this very day by Jewish scribes, namely, Kiryat Sefer, a two-volume compendium outlining the rules governing the orthography that is to be adhered to when writing Torah scrolls. He also wrote several minor works, including a commentary to Avot whose introduction includes a recording of the chain of tradition from Moses through the Tanaim.
Halakhic positions
Meiri's commentary is noted for its position on the status of gentiles in Jewish law, asserting that discriminatory laws and statements found in the Talmud only applied to the idolatrous nations of old. According to J. David Bleich, "the Christianity presented so favorably by Me’iri was not an orthodox Trinitarianism but a Christianity that espoused a theology formally branded heretical by the Church". However, Yaakov Elman argued that Bleich had no sources for this assertion.
