The article deals with the Soviet state policy of repression towards religious organizations in BM ASSR (Buryat-Mongol Autonomous Soviet Socialist Republic). Particular attention is paid to the biography of the Old Believer Athanasius bishop of Tarbagatai, Irkustk-Amur and the Far East, who was an example of fortitude and humility throughout his life. Using the materials of the memorial books of victims of political repression in the Republic of Buryatia, as well as the archive of Federal Security Service of the Republic of Buryatia the author gives a comparative analysis of the sources and comes to a conclusion that the fate of Bishop Athanasius was not unique unfortunately. Thousands of clerics of various denominations were arrested, killed or subjected to imprisonment in the camp for their faith.