Are there religious overtones?

Francis Bret Harte’s short story “The Outcasts of Poker Flat” follows protagonist Mr. Oakhurst in a tiny Western town that seeks to rid itself of undesirable, immoral people like him.
The religious aspect of the story is introduced in the first paragraph, when the narrator describes a “Sabbath lull in the air.” This might suggest a form of quiet stillness that often befalls a small town after the holy day’s church services have ended. The narrator also notes that this is uncharacteristic of Poker Flat, which is “unused to Sabbath influences.” This indicates that the people of Poker Flat have suddenly become righteous, when they did not care before.
This carries over into the expulsion of the undesirables—Mr. Oakhurst included. The narrator states that the town’s fervent moral movement is “quite as lawless and ungovernable as any of the acts that had provoked it.” The townspeople have hanged some people they disliked for somewhat arbitrary reasons, and banished others. This connects to punishment of religious heretics. Historically, heretics were tortured and/or killed for supposedly violating religious order. Harte is likely emphasizing the hypocrisy of religious people who punish others with a zeal that is just as immoral as whatever sins of which the punished is accused.
After being trapped in the cabin during a snowstorm, Oakhurst and the rest sing a refrain that mentions one who is “bound to die in His army.” This is a religious hymn that foreshadows what happens to the group, but it also suggests that the outcasts are not altogether bad people like the town of Poker Flat judges them to be. In fact, the often-rude madam Mother Shipton literally sacrifices herself so that Piney can survive—proving that a so-called immoral person can accomplish noble acts of selflessness. The image of the Duchess and Piney embracing in death at the end of the story communicates the religious message: the lawmen of Poker Flat cannot distinguish which of the two women was “she that had sinned.” This shows that the outcasts and the young innocents in the story—Piney and Tom—are equal in terms of morality and worth as human beings.
Therefore, Harte’s religious elements in the story underscore the themes of hypocrisy, judgment, and redemption.