Once more, Horwitz left his seclusion and founded a network of kollels in 20 Polish and Russian towns, among them Shavli, Dvinsk, Minsk, Warsaw, Berditchev, Novardok, Odessa, Lida and Zetl. Once a kollel was established, he would urge his students to establish adjoining yeshivas. The institutions were financed by Rabbi Lachman and headed by Rabbi Yitzchak Blazer. The Yeshiva in Berdichev had two hundred students. When Horwitz heard the pupils arguing at a difficult study or discussion, he did not leave until the matter was settled (Rabbi Dov Katz wrote about this subject in his book “"Tnuat Musar"” (“"The Musar Movement"”) p. 199).