Known by the acronym of his name, the Radbaz, a talmudic scholar, halakhic authority, and kabbalist was born in Spain into a wealthy family, but by the age of 13 was in Safed learning Torah. He moved to Jerusalem but shortly before 1513 emigrated to Egypt, apparently due to bad economic conditions in Eretz Yisrael. There he stayed for 40 years, first in Alexandria, then in Cairo where he became the official head of Egyptian Jewry. He was not only dayyan but also head of a yeshivah, trustee of the hekdesh, and administrator of charity collections. He held all of these offices in an honorary capacity, as he was financially independent. Apart from his inherited wealth, the Radbaz was apparently successful in business and as a moneylender to non-Jews. His library, containing rare manuscripts, was famous. His was an open house; Rabbi Isaac Akrish lived there for many years and was the tutor of his children and grandchildren. The Radbaz exercised a great influence upon his contemporaries, which can be seen from his success in settling a quarrel between the Mustarabs (the indigenous Jewish community) and the Maghrabis (the community with origins in other parts of North Africa), and in issuing many ordinances beneficial to Egyptian Jewry. The most famous of them are: the abolition of the dating of legal documents according to the Seleucid era (minyan shetarot), and its replacement by dating according to the era of Creation (see Calendar); formation of a chevra kaddisha (burial society; previously the dead had to be buried secretly to avoid attacks from the non-Jews); and the prohibition of the employment of non-Jews as dancers and musicians at Jewish weddings. He also tried to reintroduce into the public liturgy the recital of the Amidah by both the congregation and the reader (from the time of Maimonides this had been said by the reader only). His methods were scientific. He examined texts critically, comparing the different versions and tracing them back to their original sources, investigating their authenticity, and emending them only when necessary and no other solution could be found. Although he was a kabbalist, he introduced Kabbalah in decisions only when not in contradiction with the Talmud, or where no definite decision is laid down in the Talmud. When Kabbalah conflicted with the Talmud preference was to be given to the latter. His reputation extended beyond the boundaries of Egypt and legal and religious questions were sent to him from many communities. The Radbaz often engaged in disputations with Muslim and Karaite scholars, and his initially lenient attitude to the Karaites became more stringent. Shortly before 1553 he decided to return to Palestine. He settled first in Jerusalem where he was dissatisfied with the local governor as well as with some of the Jews, and moved to Safed, where he remained until his death.