With the consent of his teacher, R. Moses Sofer, Horowitz agreed in 1863 to the performance of the mezizah by a sponge (Yad Eleazar, no. 55). He collaborated with R. I. N. Mannheimer in the campaign for abolishing the oath more judaico and with him took an active part in the revolution of 1848. At that time he issued a call to the Jews of Austria asking for an improvement in the political and social conditions of the Jews, proposing as well that they be encouraged to take up agriculture. R. Horowitz was favored by the archduchess Maria Dorothea, who was interested in Hebrew literature and believed in the return of the Jewish people to Erez Israel. At his urging she averted the expulsion of several hundred Jewish families from Vienna in 1851. R. Horowitz was called as an expert at the trial of Leopold Kompert, editor of the Neuzeit, over the article by Heinrich Graetz on Messianism.