Rosh Yeshiva
In his capacity as rosh yeshiva, Abba Shaul maintained a heavy teaching schedule. For four hours each morning, he lectured to students in the yeshiva; in the afternoons, he taught the laws of Shulchan Aruch to dayanim (rabbinical judges). On Friday afternoons, he gave a halakha class and question-and-answer session to a packed audience in the Ohel Rachel synagogue, and on Shabbat day he delivered a three-hour discourse in the synagogue. His diligence in Torah study was legendary; it is said that when he finished delivering a shiur, he was soaked with perspiration.
Abba Shaul was also well-versed in kabbalah. At first he learned privately on Friday nights. In the 1960s, however, seeing that the knowledge of kabbalah study was waning, he gathered a group of kabbalists and founded the Emet VeShalom Yeshiva for learning kabbalah at night. Once a year, on the yahrtzeit of the Rashash, he joined the group and showed his fluency in this esoteric wisdom.
He also penned thousands of halakhic responsa in response to queries from the public at large, covering a broad range of topics. Some of his responsa are printed in his sefer, She'eilot U'Teshuvot Ohr LeZion, and he is quoted in the responsa of Rabbi Ovadiah Yosef, who remained his good friend.
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