Redemptionism is a religion based on Christianity, though it doesn't acknowledge it.
It's a simple religion for commoners to join and get behind, as the true, disturbing details of this cult-like organization are only for monks and nuns to concern themselves with. Redemptionism involves one divine creator, claimed to need daily worship, which is the only criteria the public is told to obey as to ensure their entry into an afterlife paradise; assumed to be like Christianity's Eden.
Redemptionists respect everything their god created, while that which they deem the work of demons is met with violent hostility.
It was first mentioned in the story, A Sacrifice for a Servant, from the Sacrifices That Lived series.
Following
Redemptionism is niche, yet dominant in certain rural parts of the world. It's easily confused for most other Abrahamic religions, since only "the Served" practise it as intended.
The Redeemed
"The Redeemed" is the name given to commoners who subscribe to the religion. They themselves are not familiar with the term, which is only used by the Served, and call themselves "Redemptionists". They enjoy a leisure variant of the belief and are purposely left clueless about what goes on inside the walls of their nearest convent or monastery.
Like devoted religious people do, they pray a few times a day. Redeemed are told that to be the only requirement necessary to grant them access to the afterlife. Nevertheless, since their holy practitioners present themselves as selfless, humble, and kind, many feel inclined to return the favour and are extremely generous to a nun or monk in need. They're not instructed to help The Served, or even show them an inkling of respect, but The Redeemed agree with each other their god would likely want it.
The Served
"The Served", a term not known by the general public, are the holy men and women who've fully devoted themselves to the true nature of Redemptionism -kept secret from the outside world.
Monks and nuns believe to be fighting for everyone's chance at finding Heaven and Redemptionism is seemingly inspired by the crucifixion of Jesus Christ. Having that said, Served purposely make themselves suffer in order to "absorb and then wash away the sins of humanity", more specifically, task themselves to erase the sins of less committed followers and non-believers by living a life devoid of Earthy pleasures and self-exploration.
Served are forbidden to feel joy or satisfaction from anything unrelated to the religion, and they may not establish a meaningful relationship with man or beast, only the divine. Interactions are required to stay basic and they're not to know those around them intimately, or at all, except for people's first name and position within the monastery or convent, which is also their home for life. Every resident has a small living space of their own, that caters to their survival needs, giving them less reason to wander through the hallways and engage with their peers.
Besides living emotionally and socially stunted lives, they're also expected to beat themselves to near-death whenever a large man-made disaster occurs, like war or the destruction of nature. Nevertheless, since there's no benefit in endangering the existence of the religion by mass-killing themselves, usually one monk or nun in the community is chosen to carry this burden and the leader might block news reports on purpose during extreme and long-lasting situations.
Every convent and monastery is openly advertised as a baby safe haven, which they need to in order to gain "new members" and keep their number of residents high. Since it's a difficult religion to devote oneself to, monks and nuns are usually orphaned babies raised by other monks and nuns. It seldom happens that people from the outside join Redemptionism as a holy practitioner, as the unfamiliarity with its hardships make them more inclined to question the teachings and quit -only jeopardizing the religion if the ex-student chooses to speak up about what they witnessed.
Served have strict rules and don't shy away from torturing their own or handing out the death penalty. Punishable actions are primarily the abandonment of one's religion/position, engaging in a pastime considered "demonic", or protecting a demon.
The Redeemed, on the other hand, are forgiven with a smile for any wrongdoing they might commit and the common public is always treated with understanding, making it so that any law enforcement who catches wind of something being off in the Served community is jumped by outsiders who advocate for their kindness and integrity.