In Samoilovka, thanks to the efforts of the parishioners, the Assumption Church was built by 1817. It had, in addition to the main altar of the Assumption of the Mother of God, two chapels: the right one dedicated to Saint Nicholas the Wonderworker, and the left one in honor of the Blessed Prince Alexander Nevsky. Documents from 1872 mention the left chapel: "By the resolution of His Grace on August 14, 1872, the clergy and parishioners were allowed to repair the damages in the main Assumption church caused by lightning and to install stoves in the chapels of Saint Nicholas and Blessed Prince Alexander Nevsky at the expense of the parishioners." The exact date of the abolition of the left chapel is unknown, but the Clerical Record of 1912 lists only two altars: the main altar of the Assumption of the Mother of God and the right altar of Saint Nicholas the Wonderworker, indicating the abolition of the Alexander Nevsky chapel.

Initially, the church staff included two priests and two psalmists. The deacon vacancy was opened on November 24, 1886, by the resolution of Bishop Pavel Vilchinsky. In the 19th and early 20th centuries, the priests of the Assumption Church included: Andrei Semyonovich Strokov, Nikolai Andreevich Tsvetkov, the archpriest, Fyodor Elpidiforovich Mirandov, the archpriest, Ivan Lvovich Pitayevsky, Grigory Elpidiforovich Mirandov, priest at the deacon vacancy Pyotr Grigoryevich Afinsky, and Alexey Mikhailovich Lebedev.

Houses for clergy and church servants were built on church land allocated by the parishioners and belonged to the church. Other church buildings included a stone fence, a two-story watchman's lodge, a barn, and a shop in the market square, which was rented out for the benefit of the church.

In 1841, the church was visited by Bishop of Saratov and Tsaritsyn Yakov Vecherkov, who recommended opening a school for boys from the settlements of Three Islands and Elan. Thanks to the efforts of Archpriest Andrei Strokov and board member Timofey Slozhinitsyn, the watchman's lodge was repaired, where the first students were accepted on September 15, 1843. The teaching of reading and writing to the children was conducted by priest A. Strokov and deacon of the Nicholas Church Alexey Kashinsky.