Belarusian Roman Catholic priests like Fr. Vincent Hadleŭski who promoted Belarusian language in the church and Belarusian national awareness were also under serious pressure by the Polish regime and the leadership of the Catholic Church in Poland. The Polish Catholic Church issued documents to priests prohibiting the usage of the Belarusian language rather than Polish language in Churches and Catholic Sunday Schools in West Belarus. A 1921 Warsaw-published instruction of the Polish Catholic Church criticized the priests introducing the Belarusian language in religious life: “"They want to switch from the rich Polish language to a language that the people themselves call simple and shabby"”.