In 1866 he received the title of "royal musical director." Shortly afterward, he was appointed choirmaster in the Neue Synagoge, Berlin, for which he composed the entire musical service. The Neue Synagogue was what would then have been called a conservative synagogue and what now would be considered progressive. His arrangements of ancient Hebrew melodies for choir, cantor, and organ are considered masterly productions, characterized by great simplicity and a profound religious sentiment. Many of Lewandowski's pupils became prominent cantors. Lewandowski was the principal founder of the Institute for Aged and Indigent Musicians, an institution that prospered under his management.