His Hasidic father, awed by the putative power of the sitre akhre, the dark side of Creation, was constantly at loggerheads with his misnaged
mother, contemptuous of all phenomena incapable of logical explanation.
He spoke fluent, richly idiomatic Yiddish and, like Bashevis, had grown up in a strictly orthodox home, complete with one grandfather who was a khosid and one grandfather who was a misnaged
(an opponent of Hasidism); he understood the milieu that Bashevis had created.
This opponent is called a misnaged in Peretz's story, which doesn't mean he was not religious like me.
The misnaged steals into the rabbi's house at night, hides under his bed no less, hears the other members of the household as they arise after midnight to go to the synagogue, and actually sees the rabbi get up from bed after all the others have left.
The misnaged follows the rabbi furtively into a forest where the rabbi chops wood with his ax and ties up a bundle of firewood with his rope.
When the opponent, the unbeliever in Hasidism, the misnaged, returns to the shtetl the next day at high noon, he's accosted by swarms of Hasidic followers of the rabbi.