In 1890, Nadel moved from Lithuania to Germany. At the age of 12, Nadel studied in Königsberg, Germany, under the cantor Eduard Birnbaum. He also studied with conductor and composer Robert Schwalm.
In 1895, when he was 17 years old, he moved to Berlin and enrolled in the Hochschule für die Wissenschaft des Judentums. He studied with composer Ludwig Mendelssohn and Max Lowengard.
After graduating he worked at the Kottbusser Ufer Synagogue (Synagoge am Kottbusser Ufer) as an educator and choirmaster. In 1916, he became choir director of the Jewish community of Berlin which included the supervision of music at all Berlin synagogues.
Nadel was also a very prolific playwright and poet. Starting in 1918, Nadel took up painting as well, painting several self-portraits and biblical scenes.
In 1922, at the request of Jewish leadership, Nadel worked for years on an anthology of synagogue music, Kompendium Hallelujah! Gesänge für den jüdischen Gottesdienst, which he finished in 1938 and intended to publish in seven volumes.
Before he was deported, Nadel was able to leave his large collection of old Jewish liturgical materials with a non-Jewish neighbor, some of which survived and were purchased by his friend Eric Mandell. What remains of these materials is held at Gratz College in Philadelphia
