Are the Houses catholic ??
I am not saying there isn't a huge really catholic influence on this series, there is so much of that.
But in the story, John is god. That (and the locked tomb/Alecto for the ninth) is who they are worshipping. Not the God from the bible.
Their sacred texts would not be the Bible but stories about John's resurrection but at the same time Harrow and Gideon both know the book of Ruth enough to quote it to each other. "It is finished" is literally said by Mercymorn, Pal quotes the book of Daniel in the unwanted Guest.
What is the religion in the locked tomb actually ?
I'm so sorry, OP, but you've just unlocked an unskippable cutscene...
What we can probably say about House religion:
Their overarching theology draws heavily on the Book of Revelation. Specifically, the first and second resurrections of Revelation 20. Housers are "the Children of the Resurrection", the only people (re)made in the image of God, Alecto is "the devil" locked away, whose release will herald the end.
John is God, but they don't seem to practice monotheism as classically understood: i.e. a single god that is omnipotent, omniscient, omnificent, etc. Abigail justifies her heresy by pointing out that John "never claimed omnipotence", Teacher prays that "nothing happen that [John] did not anticipate", and it's not clear whether "the Creator" referenced in the letter read at the muster is to be understood as John or as referencing some greater creation mythos.
They seem to believe in intercessory prayer, but also pray for the Emperor's needs in the same way Catholics pray for the Pope in the Ninth.
They have a concept of sin, and possibly a sacramental system.
There has been some theological development over the course of the empire: Harrow says "it has been thousands of years since anybody bothered to believe in the River Beyond" - House religion seems to have started out with something much more like the Catholic understanding of a tripartite afterlife, with hell, a purgatory that one moves through depending on one's degree of sinfullness, and a heaven. This belief now seems to be something that would get you in trouble with the authorities, and the orthodoxy is rather more like the classical underworld.
They have some kind of religious book, "the Tome". It's unclear whether this is a broader collection of scriptures (perhaps including elements from the Christian Bible) or whether it is solely a collection of religious law - the Eighth are "Keepers of the Tome" and enforce "the justice of the Tome". But it's hard to say whether any of the Bible quotes we get in the series are coming from in world scriptures or religious knowledge, whether they're appearing in the same liminal contexts as Shakespeare quotes do, or a secret third thing.
There is...possibly...some cruciform imagery in House religious iconography, depending on how you read the description of the Mithraeum chapel.
Interesting context to all this is that John was, as far as we can tell from what he tells us, educated in an Anglican school and baptised as a teenager at a non-denominational music festival (in a brief period of belief? A desire to fit in?). Some of his friends in the cow dome were nominally from various Commonwealth Protestantisms. But the only Catholic influence he definitively had was the nun, who seems to have been pushing a very specific metaphysical agenda and who John cautiously and ironically vindicates: "that finding it - the last link between what made someone alive and what made someone dead - would bring us closer to God. She was right, but I'm not sure she was right in the way she meant." The Houses are so very Catholic in part, I suspect, because there was a specifically Catholic context to John's traumatic apotheosis, and because death, resurrection, and memory wipe didn't seem to take the edge off Cristabel's enthusiasm...
But I desperately want more details about what Housers actually believe and what that looks like in peoples' lives.
(I've got further focused and unfocused thoughts on House religion here, if you're interested).
@katakaluptastrophy as someone dating an Anglican (#livedexperience) it is still a very catholic religion. my boyfriend describes it as the culturally English form of Catholicism---many regions had very distinct Catholicisms that the Roman Catholic tried to stamp down on over time with varying degrees of success (and many of these lasted far after the Protestant Reformation, though that was the impetus for many areas that already had poor relations with Rome to just hit da bricks). i was going to cite how long it took to establish celibacy in the english church as an example, but after some research it seems this was a fairly universal trend...i was mislead by St Dunstan. there are a lot of "anglican catholic" churches that follow roman catholic as well as anglican orthodoxy because they believe the anglican church IS still a part of the catholic church (in the original meaning of the universal catholic church in line with early christian belief, not as a shortened form of roman catholic...and its own can of worms). now that the archbishop of canterbury is a woman this is kind of an awkward position to take.
in my personal (and largely uninformed opinion) anglicanism shares a lot with roman catholicism in terms of structure (ordained priests who do it as their job, bishops, One Guy in Charge*), liturgy, and doctrine...sometimes, because Anglicanism allows a lot of variation in liturgy and a lot of disagreement about doctrine and its proper interpretation. ironically, the 39 articles of religion that set out the differences between catholicism and anglicanism were intentionally written ambiguously, which allows anglo-catholics to interpret them as in line with catholicism. anglicanism is sometimes understood as the "via media" or the middle path between protestantism and catholicism, and the Anglican church often describes itself as "catholic and reformed."
debate about whether/how much anglicanism is catholic(ism) aside, one of the more interesting differences for tlt purposes is that confession is practiced much more rarely, and nearly always face-to-face rather than through the lattice of the booth (a small amount of anglo-catholics being the exception). like catholicism, confessions are under a seal; whether it is a sacrament like catholicism depends on your definition of sacrament. additionally, the belief (i think) is that confession is to God directly, the priest is just your spiritual guide and advisor (which is why the "corporate confession" as a part of general prayer during the liturgy serves the same purpose as the "auricular confession" described above). the common phrase is "all may, some should, none must."
another big difference is saints, which the anglican church kind of has---they continue to honor martyrs, and consider pre-reformation saints saints, but intercessional prayer to them is rare, so the whole concept has a fairly different tenor. it also varies a lottt individually.
finally, the Book of Common Prayer/the foundational text of the liturgy has lotsss of approved variations, many of which are national---and one of, if not the, most theologically liberal and culturally ecumenical versions is the New Zealand Prayer Book/He Karakia Mihinare o Aotearoa. this bears a lot of similarity to what i vaguely remember in gideon the ninth as the traditional ninth house prayers no one else remembers or does.
