Menahem was born in Jerusalem in 1930 to his parents, Leah and Shimon Mizrahi, in a family with ten brothers and sisters. His father was a basket-weaver. He studied in cheder and Talmud Torah, and from a young age, he started working in construction and masonry, in order to help support the family.
Based on his friends’ recommendation, he joined Lehi in 1947. Aft first, he joined anti-British operations, mainly attacking the Russian Compound, where many of the Mandatory offices were located. As the Arabs began their attacks in Jerusalem, he fought in Der Yassin, Romema, Lifta, Sheikh Badr and Katamon. He also was in the battle for the Old City and the capture of the Taunus Building. He was injured a number of times, and one time, as he was hospitalized in Hadassah Hospital on Mount Scopus, he met his father, who had also been injured in combat. His father, who had not been told about his son’s injury, was unpleasantly surprised.
After he recovered, he returned to his Lehi activities.
After the Bernadotte assassination and the disbandment of Lehi in Jerusalem, Menahem enlisted in the IDF, serving in the Infantry Corps, in the Jerusalem Brigade. He continued serving as a reserve soldier until age 55, fighting in every war of Israel.
In 1952, he married Yafa Binyamin, and they had two daughters, a son and numerous grandchildren. Menahem and his family lived in Jerusalem, where he worked in construction.
He passed away from cancer on April 8, 1986.