Oryol Governorate
Kossov was born to the family of a village priest in the village of Androsovo, Oryol Governorate, Russia. He graduated from Oryol seminary, taught in the village school of Oryol Governorate. In 1884 he became a priest of the village of Spas-Chekryak near the town Bolkhov of Oryol Governorate. He worked there until his death in 1928.