Aaron Chorin was a Hungarian rabbi and pioneer of early religious reform. He favored the use of the organ and of prayers in the vernacular, and was instrumental in founding schools along modern lines. Chorin became a pivotal figure for reformers, although he himself still operated inside a traditional framework. He also interested himself in public affairs—he took an active part in the efforts for Jewish emancipation, and was very influential with the state authorities.

Reform Judaism, also known as Liberal Judaism or Progressive Judaism, is a major Jewish denomination that emphasizes the evolving nature of Judaism, the superiority of its ethical aspects to its ceremonial ones, and belief in a continuous revelation which is closely intertwined with human reason and not limited to the Theophany at Mount Sinai. A highly liberal strand of Judaism, it is characterized by little stress on ritual and personal observance, regarding Jewish law as non-binding and the individual Jew as autonomous, and by a great openness to external influences and progressive values.