Born in the Bronx, New York to non-observant Jewish parents, Rabbi Leff attended a local Hebrew school. When his family moved to the Greater Miami area, he decided to increase his religious observance and enrolled at the Hebrew Academy of Greater Miami. Since his learning skills were not up to par with other boys his age (fifth grade), he was placed in a third-grade class. Within two years he had caught up to his grade, and also made the decision to become Shomer Shabbat.
For high school, Rabbi Leff attended the Mesivta of Greater Miami, where he was regularly assigned to the yeshiva's most advanced shiurim. Afterwards he studied at the Telshe yeshiva in Cleveland, Ohio, where he received his semicha and became a close talmid (student) of Rabbi Mordechai Gifter
Entering the rabbinate
During a Passover visit to Miami in 1974, Rabbi Leff delivered holiday sermons at the Young Israel of Greater Miami in North Miami Beach. His sermons were so well received that after the holiday, he was invited to apply for the position of rabbi. With the encouragement of Rabbi Gifter, he accepted a one-year contract.
Rabbi Leff served as the Rav of the 300 families of Young Israel of Greater Miami for nine years. He worked with the NCSY chapter in his synagogue and also taught at the mesivta (high school) he attended as a teenager. His ability to understand both religious and secular Jews made him a popular leader and advisor.
Torah educator in Israel
In 1983, the Leff family made aliyah to Israel, where Rabbi Leff became the rav and mara d’atra (leader of the community) of Moshav Matityahu, a small settlement now adjacent to Modi'in Illit (Kiryat Sefer). Matityahu is adjacent to the newer city of Modi'in.
In addition to his communal duties, Rabbi Leff serves as rosh yeshivah of Yeshiva Gedolah Matityahu and oversees a 20-member kollel. He also teaches a group of unaffiliated Israelis who live near the moshav. Every Tisha B'Av, he opens his beth midrash to hundreds of English-speaking Jews from across Israel for an hours-long running commentary on the Kinnot.
Rav Leff's Torah shiurim are known for their depth of knowledge, personal insights, wit and humor. He has spoken about and recorded lessons on a wide range of themes, including the weekly Torah portion, Jewish philosophy, Jewish holidays, Amud Yomi, Jewish marriage, the role of women in Judaism, and current events.
Leff is a faculty member of Darchei Binah Women's School for Advanced Torah Studies, and the Jewish Learning Exchange of London. He also teaches at Seminar Yerushalayim, Neve Yerushalayim, EYAHT College of Jewish Studies for Women, Michlala Women's College, Bnot Torah, Ohr Lagolah Institute (based in Ohr Somayach, Jerusalem), Darchei Noam, and the Institute for the Training of Religious Family Counselors in Bnei Brak, among others. His regular Monday-morning shiur at the NCSY-Orthodox Union Israel Center in Jerusalem is popular among senior citizens.
Leff has been a featured speaker at the conventions of the Orthodox Union, Agudath Israel of America, Torah Umesorah, and the International Association of Jewish Outreach Programs (AJOP). He is a rabbinical consultant for the Refuah Institute and Baruch Rofeh Cholim.
He was a regular columnist for the now-defunct Jewish Women's Outlook and the English-language Yated Ne'eman (Israel).
- Outlooks and Insights On the Weekly Torah Portion (ArtScroll/Mesorah Publications, 1999).
- Shemoneh Esrei: the Depth and Beauty of our Daily Tefillah (Targum Press, 2008).
- Festivals of Life: the Depth and Meaning of the Moadim (Targum Press, 2009).
- Jewish Heritage Journey with Rabbi Leff: A Multimedia Jewish Heritage Journey to Lithuania, Poland & Belarus (Shorashim Productions and Grafix Mediaworx, distributed by Torah Educational Software).
- "About Rabbi Leff." (rabbileff.net)
- Berkowitz, Elaine. "An Interview with Rabbi Zev Leff." Where-What-When, December 2005. Archived December 12, 2007, at the Wayback Machine.
- Darchei Binah Faculty and Staff. Archived July 25, 2011, at the Wayback Machine.
- The Jewish Learning Exchange: Meet the Staff: Rabbi Zev Leff
- Sixth Annual Darche Noam Institutions Yarchei Kallah, Faculty Biographies. Archived July 28, 2011, at the Wayback Machine.
- Frankel, Mark. "Report from the Torah Umesorah Convention - Raising Maaminim in a Disbelieving World. May 22, 2008.
- 20th Annual International AJOP Convention Program Grid. Archived July 7, 2011, at the Wayback Machine.
- Refuah Institute, Rabbinic Advisors.
- Baruch Rofeh Cholim Rabbinical Board.