The article examines the mechanism of political repression against believers by the example of the case of the Moscow neocircular Old Believer clergy. The central figure of the article is the deacon of the Old Believers prayer Ivan Afanasievich Vlasov as a characteristic type of clergyman of the 1930s, a peasant by origin, who was arrested during collectivization, but did not change his faith. The investigative case under consideration is a sample ofthetrial ofthemost isolated part of Christians – Old Believers, who attractedthe close attention ofthe NKVD bodies by their isolation andthe steadfastness in faith characteristic of the Old Believers. The reason forthe arrest wasthetestimony of a previously arrested Old Believer priest, which coincided in time with the death of one of the neocircular hierarchs – Bishop Gennady (Lakomkin). As a result, seven non-Orthodox Old Believers were repressed, among whom were clergymen, active members of the community and one bishop. At the beginning of July 1937, all of them were sentenced to different types and terms of punishment, the most severe of which was five years of correctional labor camps. The article claims that if the case against the Old Believers-neokruzhniki dragged on for three weeks, and was considered after the entry into force of the NKVD order “On the operation to repress former kulaks, criminals and other anti-Soviet elements” of July 30, 1937,”which marked the beginning of the period of the Great Terror, the sentences would have become heavier.