Yisrael Aryeh Leib (“Leibel”) Schneerson was born in Nikolayev, Ukraine, on 21 Iyar, 5666 (May 16, 1906), the youngest of Rabbi Levi Yitzchak and Rebbetzin Chana Schneerson’s three sons. Known as Leibel, he was four years younger than the eldest child, Menachem Mendel, who would go on to become the seventh Rebbe of Chabad-Lubavitch.

In 1906, Rabbi Levi Yitzchak was offered a rabbinic position that required a secular diploma. In addition to his regular Judaic studies, he spent the months leading up to Leibel’s birth studying Russian. When he arrived in Kiev for the exam, however, he saw that the curriculum required him to learn Old Church Slavonic and Christian scripture. “He didn’t even register for the examinations, and left town that same night, arriving home on the day of [Leibel’s] brit,” his mother would recall.1

Even as a young boy, Leibel was acclaimed for his sharp mind and assiduous nature.

When he was only 8 years old, his paternal grandfather, Rabbi Baruch Shneur Schneerson, proudly told his relative, the fifth Chabad Rebbe, about his young grandson who “shows tendencies of genius, fluent in Talmud and Midrash and able to study very well.”2

His childhood friend, Yeshayahu Sher (1907-2000), recalled visiting his friend and spending time in the room he shared with his brothers, which was crammed with volumes of Talmud, Chassidic texts, and other sacred books, and the walls postered with astronomy charts.3

Yeshayahu remembered Leibel as the tallest of the three Schneerson brothers, and at the time he knew him he was just beginning to grow a beard, which did not yet cover his entire chin. Yeshayahu recalled sneaking out one spring day to play with the Schneerson boys, who welcomed the break from their rigorous study regimen that began midmorning and typically ended late at night.

During the mid-1920s, Leibel spent time in Leningrad (St. Petersburg), where the Sixth Rebbe, Rabbi Yosef Yitzchak Schneersohn, of righteous memory, had established his court. The Sixth Rebbe cherished his presence, as did the chassidim who enjoyed engaging with him and presenting questions to him.4

In 1930 he escaped the USSR for Berlin, where he was reunited with his brother, the future Rebbe. In order to duck under the Iron Curtain, he assumed the name Mark Gurary.

He relocated to British Mandatory Palestine in 1933, and married Regina (Devorah) Milgrom in 1939. In 1944, they were blessed with a daughter, whom they named Dalya.

While in Israel, R. Yisrael Aryeh Leib worked as a librarian and at one point operated a clothing store. He was in close contact with the members of the Chabad community in Tel Aviv, including his childhood friend, R. Nochum Goldshmid.

In 1950 the family moved to Liverpool, where R. Yisrael Arye Leib was to complete his doctoral thesis in the Department of Theoretical Physics of the University of Liverpool.

Tragically, he passed away on 13 Iyar, 5712 (1952). Upon hearing the bitter news, the Rebbe went to great lengths to shield his mother from learning of the tragedy, which he feared would negatively impact her health.

At the Rebbe’s directive, R. Yisrael Aryeh Leib was buried in the historic Chabad portion of the ancient cemetery in Safed, Israel.

Since R. Yisrael Aryeh Leib did not leave a son to say Kaddish for him, the Rebbe himself would do so annually on 13 Iyar, and occasionally also delivered an original Chassidic discourse in honor of the occasion.

In 1964, the Rebbe sponsored a synagogue and yeshiva complex in the Israeli city of Kiryat Ono in memory of his brother.

In the 1970s, the Rebbe asked Professor Paul Rosenbloom to work through an unfinished mathematical paper by his late brother, which was subsequently published in the Journal of Approximation Theory.

On various occasions, the Rebbe would derive lessons from the inner meaning of his brother’s name. Here is one:

Yisrael can be seen as an acronym for yesh shishim ribuy otiyot laTorah,5 there are 600,000 letters in the Torah, which teaches us that each of the 600,000 Jewish primary souls is rooted in the Torah. This mandates that every Jew live according to the Torah’s teachings and instructions.

Aryeh is a lion, which calls to mind the rabbinic directive to “be strong as a lion to do the will of your Father in Heaven.”6 No matter what challenges come our way, we are mandated to rise above them and prevail.

Leib is the Yiddish (German) translation of Lion, indicating that our strength and conviction must extend to all areas, even the mundane.7