In the future there is One religion. It incorporates all existing religions and all religions to come. In it you’re free to choose who you worship, how you worship, and where you worship. You’re free to choose whether you worship at all. You can choose the doctrines you like, free to mix and match, or you can choose none of them. You can even make your own doctrines. Your god can be a man/woman/beast/alien. They can be many or just one. You’re free to believe there isn’t god. It’s up to you. As long as you open your heart and accept the One religion you can believe whatever you like.

The One religion is, for all intents and purposes, infinite in its scope¹, stretching endlessly out across the universe, ever expanding as its missionaries pinball from one galaxy to the next propelled by a seemingly singular purpose².

The missionaries appear to different civilisations in different forms. They’re generally regarded as angels or aliens, though they do not speak of what they truly are or where they come from.

When they first make contact with a civilisation they explain — through the most suitable medium; e.g. burning bush, second coming, televangelism — that everything the civilisation already believes is true, but it’s just a fraction of the truth. Depending on their surroundings, they use different metaphors to explain how an existing religion fits into the One religion — it could be an iceberg with its tip just above water or a tree with its roots deep below ground; it could be the minute threads of a rich tapestry. Usually it’s none of these things as they’re completely alien to the prospective flock, but you get the idea. The gist of it is that the civilisation’s beliefs are just a small part of the whole — the whole being the One religion — so that their beliefs, while true, are just a fraction of the whole truth. The whole truth is infinite and unfathomable. The most common metaphor the missionaries use to illustrate this is the vastness of space, which is, quite literally, universal.

The missionaries, then expand the mythos of the One religion³, outlining a vague plot set on a stage of cosmic proportions involving some ambiguous events which span a boundless passage of time. It’s a saga which generally inspires feelings of awe and a sense of “Oneness”. As expected, interpretations of the religious materials differ greatly. Some see them as life affirming, others as prophecies of doom. Either way, most are content to infer sense where there may be none and seem to have little issue folding some new beliefs in to their old ones.

By assimilating a civilisation’s religion(s) into the One religion, it often allows the missionaries to indoctrinate whole planets, systems and galaxies with minimal opposition. A civilisation’s acceptance of the One religion generally depends on the disparity between the missionaries’ technology and their own. The optimal Indoctrination Grade of a civilisation’s technology is somewhere between Digital and Intergalactic.

If a civilisation is large enough and has a sufficiently advanced network in place, the missionaries can utilise it to reach the entire population of a given system in mere days. If there is no such network in place, it becomes a painstaking task of locating each civilisation individually and indoctrinating them one at a time. Depending on the size and population of a system, this can take literal ages.  On the other hand, if a civilisation is too advanced, they may contest the veracity of the One religion, questioning the “divinity” of the missionaries’ technology, believing themselves exceptional enough to choose their own faith.

The missionaries have tools at their disposal to accelerate the indoctrination process. They can initiate miracles or load up some wrath. They typically try to avoid eroding civilisations during the process but have no qualms if necessary. It’s of no great concern to them, who, one way or another, will make the people see the light (or lack-thereof, depending on the civilisation’s pre-existing beliefs). Once a civilisation accepts the One religion as their one religion, the missionaries adorn all places of worship/non-worship (ie. temples, government buildings, 7/11s) with the sacred symbol — a large “O” — leaving them, other than that, untouched. It’s generally believed that the circle/O symbolises the all-encompassing nature of the One religion. It’s also the first letter in the word “One”.

Because the One religion grants such a wide variety of choice, countless sects have formed within it. There are whole systems who believe Jesus was the prophet, and others who think Jesus was cool but categorically not the prophet. Some worship their sun and others believe in something completely alien (to us). There are ancient rituals and contemporary ones. There are small groups who believe their barman is the son of god, and individuals who believe it’s their dog (/alien equivalent of a dog). There are no two individuals who hold the exact same beliefs or practice them in the exact same way. Even within sects, no matter how dogmatic the traditions, there exist minute differences, often too small to observe but there nonetheless. Some sects share ideals and beliefs, others don’t. Ironically, those that do are often more opposed to one another than those that don’t. Go figure.

The One religion does not create a utopia and, like all religions, there exists infighting. Take for example, if someone believes in an early morning call to prayer and their neighbour believes in lie-ins — well, you can see the issues that may arise. Now picture that on an intergalactic scale. The One religion never takes sides, seemingly unconcerned with petty squabbling — and really, on an intergalactic scale, that’s just what it is. If, however, any conflict threatens to upset the balance of the universe, the missionaries may intervene with some strategically placed wrath.

The One Religion has holy days every day of every year, most days having more than one. You’re free to celebrate these how you see fit, though it’s up to you to book the time off work.

There’s just one commandment in the One religion — thou shalt never doubt the One religion. Every so often someone takes it upon themselves to question the veracity of the One religion, emboldened by hubris and absenteeism. Entire populations have vanished overnight after positing their incredulity or suspicion, their fate unexplained, though widely known: somewhere in the mythos there’s a brief mention of hell⁴.

Hell is currently a system formerly known as HL4724⁵ situated in the Triangulum galaxy. It’s a barren system devoid of comforts where heretics are free to live as they please. Some heretics see hell as a chance to develop a civilised society free from hegemony, though the lack of resources means it generally devolves into a standard order post-apocalyptic Lord–of–the–Flies-meets-Mad–Max type scenario. When not struggling for survival, or engaging in Thunderdome-style bloodsports, most heretics spend their time further scrutinising the One religion, as it’s the only place in the One Religion’s domain where they can do so freely. Because no one knows its origins or goals, many theories have been formed — the top five are currently:

5. The missionaries have no ulterior motives.
4. The missionaries are unifying the universe to strengthen it against a coming threat.
3. The missionaries are laying the groundwork for the creator of the One religion’s own universe-scale invasion.
2. The One religion is a front for an intergalactic, deep-state child-sex ring.
1. Lizard people.

When heretics get tired of the wholly inconclusive conjecture and bland cuisine they generally wish to leave hell⁶, which they’re free to do, once they finally accept the One religion as their one religion⁷. Once returned to their respective civilisations, ex-heretic’s lives largely fall into two camps: camp A — born again converts who are fervent on rejuvenating their interpretation of the faith wherever they go, and camp B — people who never mention the One religion again. Some return hardened by their experience while others come back broken. Everyone returns a little more cultured, having met a sizeable swath of the universe in hell.

There is no mention of heaven in the mythos, though again, this leads to far more conjecture than if there were.

The One Religion is all things to all people, its endless utilities assumed by its practicer. It can nurture purpose and order where there was none; it can incite war where once there was peace; it can create comfort in the cold void of the universe and it can instil fear in the heart’s of its believers. It can do all of these things at once. It can be utilised for good and for evil, though which is which is eternally unclear. In some parts of the universe it’s the loudest voice, in others it’s the background chatter in the dialogue of society.

Being all things to all people, the One religion has a perceived longevity, though, like all things, it too will inevitably fade, its Oneness crumbling into manyness. Or it will be assimilated, as it assimilated so many other religions. Or it will be wiped out along with everything else, leaving the mysteries of time and space unsolved. 

Indices
¹ No one really knows where its influence begins or ends.
² And most likely, a fission based fuel source.
³ The distribution method for such sacred data varies — it can be anything from stone tablets, to printed pamphlets, to mass-telepathy.
⁴ Though it is known by many names.
⁵ Once HL4724 reaches maximum capacity a new hell will be assigned.
⁶ Some people choose to stay in hell, having found their calling in life.
⁷ Accepting the One religion is the only proven way out of hell, though there have been countless failed attempts.