ENThe activity of the Basilian congregation is crucial to understanding the cultural, social, religious transformations and relations occurring at the cultural borderlands marked by the Latin and Byzantine cultural circles. Based on the catalogue of Basilians studying at the papal seminary in Vilnius between 1611 and 1795, and a census of the monks from 1800, the paper analyses the linguistic competences of the Basilians of the Lithuanian province. The monks usually had knowledge of three languages i.e., Latin, Polish and "Sclavonica" or "Ruthenica". In the second half of the 18th century, Basilians expanded their linguistic competences to include knowledge of modern languages: French, German and Italian. In response to pastoral needs, they used Lithuanian, Samogitian and Latvian. The monks used their linguistic competences in their pastoral and educational work. The monks in the Grand Duchy of Lithuania, together with the Unitarian parish clergy, formed an environment that maintained the literary tradition of the Ruthenian language. Basilians' linguistic competences shaped the forms of content and message in pastoral work, spreading faith and enabling correlations between the cultural heritage of various linguistic groups. The monks' skills enabled them to act as content intermediaries between communities of different linguistic backgrounds and between elite and egalitarian culture. Key words: Uniate Church, Basilian Order, Basilians of the Lithuanian Province, Basilian education, Ruthenian culture, Grand Duchy of Lithuania. [From the publication]