Building True Ovdei Hashem
Meet Our
Leadership and Staff
Rav Yossi Stilerman
Rosh Kollel
Originally from New York, Rav Yossi Stilerman was part of the founding group of HaRav Yitzchak Berkovits' Kollel (The Jerusalem Kollel) in 2002. After three years as a talmid, he continued for another eleven years as Rosh Chaburah, developing a reputation for his depth, clarity, and ability to inspire serious growth in his peers. In 2016, Rav Yossi became Rosh Chaburah at the Center for Kehilla Development, where he helped shape future rabbanim and communal leaders. In 2021, he co-founded Kollel Derech Chaim together with Rav Aharon Rubenstein and Reb Daniel Green, with a vision to build well-rounded ovdei Hashem equipped to lead with achrayus, halachic clarity, and inner strength. Rav Yossi is known for his unique derech in both halacha and hashkafa, and for his revolutionary approach to semicha preparation: instead of tests, avreichim write a personal kuntris, fostering long-term mastery and the ability to teach and pasken with confidence. Through his leadership, hundreds of talmidim have been empowered to take real responsibility for their learning — and their role in Klal Yisrael.
Rav Aharon Rubenstein
Mashgiach
Originally from Los Angeles, Rav Aharon Rubenstein learned in Yeshivas Zeev HaTorah and then in Yeshivas Shor Yoshuv before marrying and settling in Eretz Yisrael. He is a devoted talmid of the world-renowned Rav Mottel Zilber shlit”a, the Toldos Yehudah Stuchiner Rebbe, and masterfully gives over his derech in avodas Hashem, penimiyus haTorah, and machshava with clarity and passion. Rav Aharon delivers multiple weekly chaburahs to the kollel, including on Mesilas Yesharim, Avodas Avodah (Tosher Rebbe), and other foundational works in avodah pnimis. He also gives regular shiurim to the bochurim of Yeshivas Keser Torah (Rav Zucker’s yeshiva), where he is beloved for his depth and ability to connect on a personal level. His warmth, sincerity, and ability to guide avreichim through real-life challenges — from shalom bayis to chinuch to spiritual growth — make Rav Aharon an irreplaceable presence in the kollel.
R' Ezzy Astor
Shoel U'Meishiv
Rav Ezzy learned in Yeshivas Ohr Dovid, followed by three years in Yeshivas Zeev HaTorah and additional years in Yeshivas Mir. After marriage, he continued learning in Kollel Mir for five years and later joined Kollel Ner Naftali and Rav Wagner’s Kollel. He is a close talmid of HaRav Meir Wertziger and HaRav Doniel Belsky shlita, whose influence continues to shape his learning and approach. After joining Kollel Derech Chaim as an avreich, Rav Ezzy quickly became a valuable resource for the tzibbur and now serves as the kollel’s afternoon sho’el u’meishiv, fielding questions on the Oraysa Amud Yomi limud and beyond. His clarity in both nigleh and nistar make him a go-to address for avreichim seeking guidance. Rav Ezzy also delivers a daily Nefesh HaChaim shiur and is known for his rare ability to explain deep Torah concepts in a clear, grounded, and accessible way.
R' Aharon Knobel
Director
Originally from Miami, Aharon Shlomo has always brought a deep passion for growth — both personal and communal — to every step of his journey. After learning at Yeshivas Mevaseret and Yeshivas Bircas HaTorah in Yerushalayim, he continued his learning with Rabbi Shimon Green in Phoenix, Arizona. He then moved to Johannesburg, South Africa, where he taught at Yeshivas Maharsha High School, before returning to Miami to split his day between Torah learning and professional work. Upon moving to Eretz Yisrael with his wife, Aharon joined Kollel Derech Chaim as a full-time avreich and quickly became a driving force behind the kollel’s vision and impact. Today, he serves as the Kollel's Director, overseeing programming, development, fundraising campaigns, and community relationships — all with a clear sense of purpose and achrayus. Aharon’s unique ability to blend real-world responsibility with heartfelt dedication to Torah makes him an anchor of the kollel and a trusted leader for its future.
R' Adam Lombardo
head of development
Originally from Silver Spring, Maryland, Adam brings a rare blend of charm, warmth, and deep sincerity to everything he does. A proud alumnus of Yeshiva Gedolah of Greater Washington, Mercaz HaTorah, and Yeshivas Mir Yerushalayim, Adam spent several years as a dedicated avreich in Kollel Derech Chaim before stepping into his current role. Beloved by all who know him, Adam is the kind of person who lights up every room he enters — the life of the party and the heart of our kollel community. Now serving as Head of Development, Adam leverages his genuine personal connections and passionate belief in our mission to build lasting relationships with supporters and partners around the world.
Haim Cohen Saban
Director of Philanthropy
Haim Cohen Saban is a successful businessman and close friend of Rav Yossi Stilerman — but above all, he is a passionate supporter of Torah learning and Jewish causes. After spending many Eluls learning alongside Rav Yossi at the Jerusalem Kollel under HaRav Yitzchak Berkovits shlit”a, the two developed a deep and enduring friendship rooted in shared vision and values. Haim long dreamed of helping establish a kollel that would empower the next generation of Torah leadership without limitation. When Rav Yossi founded Kollel Derech Chaim, Haim was honored to become one of its earliest and strongest supporters — a role he holds with pride and heartfelt commitment.
R' Yaakov Bach
Director of Job Placement
Originally from Teaneck, New Jersey, Yaakov Bach attended The Frisch School before spending two years learning in Yeshivat Reishit in Eretz Yisrael. He later earned a degree in psychology from Yeshiva University. After marriage, Yaakov served as the Director of Portland NCSY, where he inspired countless teens through leadership and meaningful programming. In 2021, Yaakov founded The Tefillin Project, an initiative that gifts tefillin to committed baalei teshuva who never had the zechus to receive a pair at their bar mitzvah. He also launched The $25for25 Project, a global intercollegiate chavrusa initiative that has connected hundreds of college students to consistent Torah learning over the past four years. Yaakov’s broad network and deep familiarity with Jewish organizations around the world enable him to guide avreichim toward impactful roles after leaving kollel. His passion for Klal Yisrael, boundless energy, and unwavering commitment to others make him one of Kollel Derech Chaim’s most respected and beloved members.
Zechariah Zahler
Back Office
Manager
A close childhood friend of Rav Yossi, Zechariah is a successful businessman who devotes his time and energy to supporting Torah causes across Klal Yisrael. In addition to running multiple businesses, Zechariah plays a key role in several nonprofit organizations, including Ner Gavriel, which provides vital financial assistance to avreichim in Yeshivas Mir Yerushalayim. At Kollel Derech Chaim, Zechariah selflessly oversees the operational and financial management of the kollel. His dedication, efficiency, and behind-the-scenes leadership allow the kollel to thrive and grow — making him an indispensable part of the team and the mission.