ENThe article raises the question of the reports of the first Russian resident in the Polish-Lithuanian Commonwealth as an informative source on the history of Lithuania and Belarus, offering new questions in the study of the past of two powerful Lithuanian families. The political preferences and course of action of Krzysztof Zygmunt Pac, the Chancellor of the Grand Duchy of Lithuania, are being clarified, which in most cases acted in the interests of the leader of the “French” party, Jan III Sobieski (70-ies of the 17th century). In addition, an attempt is being made to recreate one of the symbols of the Chancellor's power – an inkwell made of gold and silver. The author also tries to find out when Wysokie Litewskie became the residence of the Grand Treasurer of Lithuania Benedykt Paweł Sapieha, ascertain that the aristocrat stayed in palace in 1677, before its reconstruction was completed. Finally, we analyze the symbolism of the salute at the feast of the Lithuanian Hetman Michał Pac, which included various benevolent symbols. Key words: archival documents, permanent diplomatic mission, Polish-Lithuanian-Russian relations, XVII century. [From the publication]