The article deals with a disappearing community of Russian Judaizers (Subbotniks) in Armenia. The analysis of the folklore repertoire of the Subbotniks allows concluding that the very experience of breaking with the religious past is a foundation of their identity. The break happened in the second part of the 20th century and was accompanied by accepting the exonym “Subbotnik” which turned into a relatively stable ethnic category. This uncommon process can be explained using the distinction between “groups” and “categories” and the opposition of “ethnic” and “religious”. The article considers the history of the use of the term “Subbotnik” and its complex connotations, referring to both Judaism and Christian sectarianism. In contrast to “ethnicity without groups,” as coined by Roger Brubaker, the Judaizers show an example of stable communities that are particularly difficult to categorize. The Subbotniks of Armenia, who emerged as a “group without categories,” are now tuning into a “category without group”. The article shows a correlation between this transformation and the substitution of textual (religious) foundations of daily practices by the ethnic ones.