Mordechai was born on October 25,1923 in Warsaw Poland. He was the sixth child of his parents Avraham Yehuda and Sarah, who had seven children. The family owned a comb manufacturing plant; both parents worked there. They were Orthodox Zionists, and Mordechai is an observant religious man to this day. The family made aliya in 1924, settling initially in Bnei-Brak. His father purchased a bus and drove passengers between Bnei- Brak and Tel Aviv, which he later sold,
returning to his old profession managing a comb factory. The family comb business still runs. Mordechai studied at a Talmud Tora of the ‘Histadrut Hacharedim’, and was a member of ‘Brit Hachashmonaim’ Tel Aviv. Around late 1938, or early 1939 he joined Etzel, and when the split occurred, joined Yair. Following Yair’s assassination, Mordechai joined the ‘Tuvya Group’ and was involved there in all fields of underground work. Along with his friends, during 1943, he joined the central body of Lehi. In 1944 he was arrested, imprisoned in Jaffa, Latrun and Akko Prisons, and a month later,transferred from there to exile in Asmara Eritrea. Mordechai remained in African exile until sent back by the British, early March 1948, and put in ‘Atlit Detention Camp’, which held at that time, all prisoners and detainees of the British, who belonged to the Undergrounds. He was released from Atlit on April 8,1948.
After establishment of the State, Mordechai joined the IDF together with all the other Lehi members, and was transferred after a short while from the 8th Brigade to the Artillery Corps. At his artillery battery, he also served as a sports instructor. After his discharge from the IDF end of 1949, he entered the plastic combs family business. On May 4,1954 Mordechai married Mazal Falkon. They have three children: Avraham, Ofira and Amir, and five grandchildren.