Between 1388 and 1392, he wrote several essays, which were later collected and entitled Regulae Veteris et Novi Testamenti ("Principles of the Old and the New Testaments").
Między 1388 a 1392 napisał kilka prac, które potem zebrano i zatytułowano Regulae Veteris et Novi Testamenti ("Zasady Starego i Nowego Testamentu").