Weinberger began his career as a rebbi at a yeshiva in Far Rockaway. He taught for two decades at Ezra Academy, a Jewish day school in Queens, and also served as a mashgiach ruchani for N'vei Tzion of Queens.
In December 1992 Weinberger became the first rabbi of Congregation Aish Kodesh in Woodmere, New York. He named the synagogue after Rabbi Kalonymus Kalman Shapira, the Piaseczna Rav and author of the work Aish Kodesh, who was a leading Polish Hasidic rabbi in prewar Europe. Noting that religious Jews may follow the letter of the law without feeling its inner joy or a personal connection with God, Weinberger preaches the tenets of Hasidism to rekindle excitement and joy in Jewish observance. He leads the congregation in song and dance after prayer services, conducts tishen, officiates at an annual hillula celebration on the yahrtzeit of the Piaseczna Rav and on Lag BaOmer, which each draw more than 1,000 attendees, and takes congregants on pilgrimages to kivrei tzaddikim in Ukraine and Israel. The synagogue building itself is modeled after a Polish Hasidic shtiebel. Congregation Aish Kodesh has been called a "phenomenon" and a "revolution" in the Modern Orthodox community of Long Island. In 2013 Weinberger was appointed mashgiach ruchani at Rabbi Isaac Elchanan Theological Seminary, where he presents weekly classes in Hasidic thought and philosophy, conducts a monthly farbrengen, and spends Shabbat on campus several times a year. Although he is considered the "senior spokesman" of the Neo-Hasidic movement, he dislikes the title. Weinberger has been noted as "one of this generation's leading teachers of Chassidus". His teachings derive from a wide range of Hasidic sources, including the Baal Shem Tov, Ramchal, Rebbe Nachman of Breslov, the Baal HaTanya, Chabad, and Izbica, as well as from the Vilna Gaon, Rabbi Tzadok Hakohen, and Rabbi Abraham Isaac Kook, among others. He also teaches works that were previously unavailable to the English-speaking public, such as the works of the Bilvavi Mishkan Evneh. He has recorded over 3,500 lectures on Hasidic thought and philosophy.
Works
In the 1980s and 1990s Weinberger wrote articles on issues pertaining to Modern Orthodox practice and baalei teshuva. He was a frequent contributor to Jewish Action, published by the Orthodox Union, and the Journal of Halacha and Contemporary Society, published by the Rabbi Jacob Joseph School. In 1990 he authored the book Jewish Outreach: Halakhic Perspectives, on halakhic issues pertaining to Orthodox Jewish outreach. Since 2011, he has produced four volumes of English translation and commentary on the Hebrew seferOros HaTeshuva by Rabbi Abraham Isaac Kook, published under the title Song of Teshuva. In 2015 a collection of his Torah discourses at the annual hillula of the Piaseczna Rav at Congregation Aish Kodesh was published under the title Warmed by the Fire of the Aish Kodesh.
Personal
Weinberger wears full Hasidic levush, including beard and peyos, Hasidic-style jacket and black hat on weekdays, and shtreimel and bekishe on Shabbat.