The Nikolskaya Church in Petrovsk was built in 1750 by the Mordovian prince Piksai Alyamasov, the founder of the village of Machkas. Its parishioners were mainly Orthodox Mordvins. The construction of a new church in honor of St. Nicholas the Wonderworker began in 1834 and was completed in 1852 thanks to the efforts of the parishioners. The church was built of stone, had a bell tower, and an altar in honor of the Archangel Michael. Two city schools and the schools of the villages of Kurnosov, Ionichev, and Larin were part of its parish. After reconstruction in 1879, the building became warm. In the 1910s, under the guidance of priest Ioann Kazantsev, the construction of a new church began, which was not completed due to the October Revolution. The church was destroyed in 1931, and its exact location in the city is unknown.