Rebbe Aharon became an acknowledged leader of Haredi Judaism in Israel. He laid the groundwork for the spread of Belzer Hasidism through the establishment of schools and yeshivas in Tel Aviv, Bnei Brak, and Jerusalem. In 1950, the Rebbe moved his court to the Jerusalem neighborhood of Katamon, and established a yeshiva there. His sights set on expanding Belz, he drew up plans for a large yeshiva and study hall in downtown Jerusalem, on a hill behind the original Shaarei Tzedek Hospital. The cornerstone was laid in 1954, and the building was completed in the summer of 1957. One month later, however, the Rebbe died.