At the start of 14th century, zhe doctor of decrees, Jan of Ostrov was one of the important figures in the court of Wenceslas II. As the Bishop of Brixen (from 1306) he was part of the Curia in Avignon.
It was here in 1320 that John XXII appointed him as one of ten consultantsin the matter of wheter magic was to be considered a herresy.