[Possible/Probable] Fuero Real (Statute Royal) of Alphonso IX. Book IV, Title 2. – On Jews [Present-day Spain / Kingdom of León and Galicia] [Provisional]: “Article I – We forbid any Jew reading or keeping concealed books opposed to his religion […]. We further prohibit their reading, or knowingly possessing any books that speak against our religion, or in disparagement of it. But we permit them to read and possess all books on their religion […]. And should a person read or keep any book contrary to this our prohibition, his person and property shall be at the mercy of our king. Article III – If a Jew utters anything reviling against God, the holy Maria or other saints, he shall be fined ten maravedis for each offense, and the king shall order one hundred lashes to be given to him. […]”
Elias H. Lindo, The History of the Jews of Spain and Portugal, 1848, page 76, Accessed online; Researched by Franziska Wagener 4/25/2016