In 1427, the Carthusian monk Heinrich Beringer complained to the Grand Master Paul von Rusdorf that the Teutonic Knights allowed Prussians to continue worshipping the old gods. When asked about this matter, the commanders were to answer: "Let Prussian be Prussians." The existence of relics of old cults is also indicated by synodal and act sources, e.g. the Toruń Peace document from 1411. Recently, Michael Brauer questioned the survival of paganism in Prussia until the 15th century. According to him, the available information was only a creation constructed by the authors of said sources. This is also the opinion of Stephen Rowell and Darius Baronas in relation to Lithuania. They do not notice, however, that it is only early-age modern sources that expand pagan pantheons and associate folk customs with paganism. In Prussia, the language situation was conducive to maintaining relics of paganism – priests did not know Prussian.