In 17th century Russia, Old Believers
unmoved in the tumult of doctrinal change,
intransigent in their long-held beliefs,
insisted on pronouncing Alleluia three times, not twice.

And, conversely, crossed themselves with two fingers, not three.
Made their processions round a church clockwise, not counterclockwise.
Accordingly, Czar Peter created an Office of Schism to hunt them down.

Which scattered to Siberian taiga and foreign lands these simple folk desperate to main their essential beliefs.