4 Tammuz · Yahrzeit
Rabbeinu Tam
Rabbi Yaakov ben Meir was a grandson of the great Rashi, and he studied under his father, Rabbi Meir ben Shmuel, and his other brother, Rabbi Shmuel ben Meir, the Rashbam.
Yahrzeit - 4 Tammuz
Resting place - Ramerupt, France
Rabbeinu Tam was born in the city of Ramerupt in 1100 to Rabbi Meir ben Shmuel; his mother, Yocheved, was the daughter of the great Rashi.
Even at a young age, Rabbeinu Tam engaged in disputes with his great grandfather (Rashi passed away when Rabbeinu Tam was only five years old).
Already in his youth he was nicknamed Tam. This word is used in the Torah to describe another Yaakov — our forefather — of whom it is said: "Yaakov ish tam" (Bereishit 25:27), which translates as "a simple, wholesome, noble man."
Rabbeinu Tam was an extremely successful wine merchant and financier, and was also highly proficient in the rules of Hebrew grammar.
Rabbeinu Tam was regarded as the greatest Torah scholar and leader of his generation, and he was called upon to resolve most of the halachic issues of his time. Scholars from around the world flocked to his yeshiva in Ramerupt (France) to hear his sharp Talmudic analysis, in which he brilliantly compared and contrasted topics, resolved difficult passages, and revealed underlying principles applicable to all of Jewish law. These lectures formed the basis of the Tosafot commentary, compiled by his students and printed in the margins of every page of the Talmud. His name is familiar to every student of the Talmud.
He frequently disagreed with the commentary of his grandfather Rashi and offered his own interpretation.
He said: "I could have written Rashi's commentary on the Talmud, but not his commentary on the Torah." He had two well-known disagreements with Rashi regarding the Torah: one concerning the placement of the mezuzah, and the other concerning the order of the parshiot contained in tefillin. It is said that Moshe Rabbeinu (Moses) himself appeared to him in a dream and told him that Rashi's opinion was correct, but Rabbeinu Tam reportedly replied: "Moshe, our Teacher, here you made a mistake."
Rabbeinu Tam corresponded with Rabbi Avraham ibn Ezra, whom he greatly admired and respected.
In 1146, when Crusaders ransacked his home, he miraculously escaped death, surviving five knife wounds to the head. A French nobleman who knew and respected him turned back the bloodthirsty mob by promising them that he would convert the rabbi to Christianity.
Tefillin According to Rabbeinu Tam
As is well known, Rabbeinu Tam fundamentally disagrees with Rashi regarding tefillin, and although the Shulchan Aruch records Rashi's opinion, many Sephardic Jews and Chassidim also put on tefillin according to the opinion of Rabbeinu Tam.
There is a difference of opinion regarding the order in which the passages (parshiot) are inserted into the batim; according to Rabbeinu Tam, the order is the reverse of Rashi's. Pious Jews put on tefillin according to both Rashi and Rabbeinu Tam.
Mezuzah According to Rabbeinu Tam
According to Rashi, a mezuzah may not be placed flat in an opening in the doorpost or simply affixed parallel to the ground. The mezuzah, in a certain sense, resembles a Torah scroll, which is kept upright, and therefore it must also be affixed upright, vertically. The Rambam and many other rishonim (sages of the early generations) hold the same view.
Rabbeinu Tam's opinion is that it is disrespectful to affix the mezuzah vertically. In his view, the mezuzah should be affixed flat, parallel to the ground.
The Shulchan Aruch (289:6) rules in accordance with the opinion of Rashi and the Rambam. Therefore, the Sephardic custom is to affix the mezuzah vertically.
However, the Rema (289:6) holds that the opinion of Rabbeinu Tam must also be taken into account, since, as mentioned above, he holds that the mezuzah may not be affixed vertically. Therefore, the Rema suggests affixing it at a slight angle. Such a placement does not contradict either opinion.
Sunset According to Rabbeinu Tam
Rabbeinu Tam established a different "method" for determining the time of sunset than had been established before him.
Sunset, and accordingly the start of the next day, "according to Rabbeinu Tam," occurs approximately half an hour later than the time accepted by other Torah authorities (their method of determining the time is usually called "according to the Geonim," that is, according to the time established by the heads of the yeshivot of the post-Talmudic period).
In modern calendars, which specify in detail the times for the start and end of Shabbat, one often finds the notations "according to the Geonim" or "according to Rabbeinu Tam."
Most communities (almost all) determine the start of Shabbat according to the Geonim. Only a few Chassidic groups follow "Rabbeinu Tam."
However, many people across various communities and movements determine the end of Shabbat "according to Rabbeinu Tam" — that is, they conclude Shabbat approximately 40 minutes later than usual.
In 1171, the Jews of the city of Blois were accused of ritual murder. Thirty-four Jews refused to convert and were burned alive. This tragedy shook the Jewish people. Rabbeinu Tam composed an elegy mourning the deaths of these martyrs. Two weeks later, on June 9, 1171, he returned his soul to his Creator.
May the merit of the tzadik protect our entire people!
(https://dailyzohar.com/tzadikim/5-Rabbi-Yaacov-ben-Meir)