Rabbi Aharon Rokeach, known as the Maharah of Belz, was born in 5640-5641 (1880), the son of Rabbi Yissachar Dov Rokeach, the third Belzer Rebbe, and of Basya Ruchama, a granddaughter of Rabbi Aharon Twersky of Chernobyl. He was his parents' first child, born after twelve years of marriage. His mother died when he was four, and he grew up under the wing of his grandfather, Rabbi Yehoshua Rokeach, the second Belzer Rebbe.

From a young age he spent most of his day in Torah study, ate and slept very little, and concealed his accomplishments with a modesty he kept all his life. On 2 Adar 5658 (1898) he married his cousin Malka, daughter of his uncle Rabbi Shmuel. When his father died in 5687 (1926), he succeeded him as Rebbe and as rabbi of the town, the last rabbi of Belz in Galicia before the Holocaust.

On Hoshana Rabbah 5700 (1939) the German army entered Belz. After completing the hakafos of Simchas Torah, he fled; he passed through the Krakow ghetto and then the Bochnia ghetto, from which he was rescued for a large ransom together with his half-brother, Rabbi Mordechai of Bilgoray. After eight months in Budapest he left Hungary and reached Eretz Yisrael on Thursday, 9 Shevat 5704 (3 February 1944). His wife and children had perished in the Holocaust.

Settling in Tel Aviv, he rebuilt Belz Chassidus in Eretz Yisrael, first in Tel Aviv and then in Jerusalem, Bnei Brak and Haifa. He was known for his holiness and wonders, and for refusing to hear anything bad about a Jew: rather than call someone a Shabbos desecrator, he would say that he "forgot the essence of Shabbos." He raised his nephew, Rabbi Yissachar Dov, son of Rabbi Mordechai, who succeeded him. His teachings were collected after his passing, notably in Maharah and Leket Imrei Kodesh.

He passed away at Shaare Zedek Hospital in Jerusalem on Motzaei Shabbos, 21 Av 5717 (18 August 1957), and is buried in the Har HaMenuchot cemetery in Jerusalem.