At The Diet Piotrków in 1538, which dealt with restrictions on the economic rights of the Jews he made a speech demanding the expulsion of the Jews from Poland. The next day (11 March 1538) he was dead. This became the basis for devising suspicion that he was poisoned. He was buried behind the altar in the Wawel Cathedral. Currently his tombstone is in King John Albert Chapel in Wawel Cathedral (formerly Bożego Ciała).Władysław Pociecha, Chojeński Jan. in Polish Biographical Dictionary. Polish Academy of Learning 1937, pp. 396–399. .
