Saúl (Shaul ben NN) was born in 13th-Century Spain to a pious Jewish family,[1] and he is believed to have been a student of Rabbi Eliezer of Tarascon.
[1] Prior to the 1263 Disputation of Barcelona, he followed Nicholas Donin's lead in attempting to ban the Talmud, which he argued had "irrational" textual material.
Through the agency of Raymond de Penyafort and with letters of protection from King James I of Aragon, he went on missionary journeys and compelled Jews everywhere to listen to his speeches and answer his questions, both in synagogues and wherever else he pleased.
He, therefore, in 1264 went to Pope Clement IV and denounced the Talmud by making assertions that it contained passages that were derogatory in regards to Jesus and Mary.
He thus persuaded the pope to issue a bull that commanded the bishop of Tarragona to submit all copies of the Talmud to scrutiny by the Dominicans and Franciscans.