Christian authorities in Europe were largely unaware of possible references to Jesus in the Talmud until 1236, when a convert from Judaism, Nicholas Donin, laid thirty-five formal charges against the Talmud before Pope Gregory IX, and these charges were brought upon rabbi Yechiel of Paris to defend at the Disputation of Paris in 1240. Yechiel's primary defence was that the Yeshu in rabbinic literature was a disciple of Joshua ben Perachiah, and not to be confused with Jesus ("Vikkuah Rabbenu Yechiel mi-Paris"). At the later Disputation of Barcelona (1263) Nahmanides made the same point. Jacob ben Meir, Jehiel ben Solomon Heilprin (17th century) and Jacob Emden (18th century) support this view.