During World War II, he famously accompanied his brother, Rebbe Aharon, on a daring escape out of Nazi-occupied Europe.

The two reached Israel in February 1944, the only surviving members of their families, and threw themselves into rebuilding the ranks of Belzer Hasidut which had been decimated by the Holocaust.

"[1] With the outbreak of World War II and the German invasion of Poland, the town of Biłgoraj was bombed from the air and most of its residents fled.

Meanwhile, Belzer Hasidim in Israel, England and the United States arranged to spirit the Rebbe out of Belz to Sokal and then to Przemyslany, where he remained for nearly a year.

With the onset of Operation Barbarossa on 22 June 1941, Sokal, on the front lines, fell to the Germans on the first day; Prezemyslany was conquered by July 1.

Thanks to the untiring efforts and cash inflow from Belzer Hasidim abroad, the Rebbe and Rabbi Mordechai managed to stay one step ahead of the Nazis in one miraculous escape attempt after another.

[2] In their most hair-raising escape attempt, the brothers were driven out of occupied Poland and into Hungary by a Hungarian counter-intelligence agent who was friendly to Jews.

The Rebbe, his attendant and Rabbi Mordechai, shorn of their distinctive beards and sidelocks, were disguised as Russian generals who had been captured at the front and were being taken to Budapest for questioning.

Rebbe Aharon and Rabbi Mordechai spent eight months in Budapest before receiving highly rationed Jewish Agency certificates to enter Israel.

Rabbi Mordechai delivered a lengthy speech combining Torah thoughts with commentary on the political situation, exhorting his audience to use their charity money to ransom Jews trapped in German-occupied Europe and also to feed and clothe those who had managed to escape to then-free Hungary.

After crossing the Bosphorus straits by ferry, they were subject to a vigorous search and debriefing by the British secret service as "aliens" from Nazi-occupied territory.

[2] On the outskirts of Beirut, they were greeted by a crowd of 200 Sephardim and 20 Israeli businessmen and hosted to a reception by local rabbis and dignitaries.

[2] Rabbi Mordechai continued to serve as his brother's right hand after the war, refusing to take a rabbinical position but dedicating his efforts to strengthening Torah Judaism and Belzer Hasidut.

At a routine foundation-stone laying for a new aron kodesh at Haifa's central beth midrash, for example, he spoke passionately and at length about the Holocaust: I have discovered that the public in the Holy Land does not fully believe the terrible horror that has befallen our nation in exile.

He was also heavily involved in helping war survivors obtain government benefits, housing and employment, and arranging weddings on their behalf.

These scraps were discovered in the home of his widow in late 2009, causing his son and current Rebbe, Rabbi Yissachar Dov, to change his levush (wardrobe) in the middle of Hanukkah.

[7] In the summer of 1949, Rebbe Aharon sent his brother on a mission to strengthen and encourage survivors and the nascent Belzer communities in Europe.

One of his relatives sat in her house for an entire day to copy the whole notebook so that his brother, Rebbe Aharon, could also benefit from his father's divrei Torah.

[4] At the end of the summer, Rabbi Mordechai told his companions that his father had appeared to him in a dream and instructed him to return home immediately.