For those who’ve been following my theories, I’ve made it clear that I don’t believe that Witch Cult Gospels direct their holders to their desired futures but actually serve to keep the world on a particular path that Pandora, Echidna, and Satella all desire.
There is a basis to believe this given that everything up until Season 2 was planned at least partially by Echidna centuries ago and probably by Flugel too given he made Petelgeuse promise to not take in the Sloth Witch Factor, which was implied by Petelgeuse apologizing to Flugel, most likely so that Petelgeuse wouldn’t until Pandora and Regulus invaded Elior Forest when he had no other choice to protect the love of his life, Fortuna, and Emilia.
As Season 2 revealed through Roswaal and Season 3 reiterated, Echidna’s not-quite-Tome of Wisdom, however many there are given Echidna might’ve lied about how many copies she made, is the prototype for the Witch Cult Gospels, meaning that they are most likely at least partially made by some of the same materials, and given how Roswaal’s not-quite-Tome of Wisdom was not meant to bring about the return of the Echidna Roswaal knew, the same could go for Gospels in not directing their holders to their goals. I don’t buy into the theory that the reason Otto wasn’t in Roswaal’s not-quite-Tome of Wisdom is ’cause he was meant to have died as Ram, Petra, and Emilia all died in Arc 3, and with that being the case, it can be argued that all three of them were meant to have died, so the true reason Otto wasn’t in the not-quite-Tome of Wisdom must have been something else. As a text that supposedly tells the future and can update itself based on current happenings, there’s no good reason why Otto was excluded unless the source of the knowledge of the Tome just didn’t want it to be included, and if that’s the case, Echidna may very well have been responsible for its contents with the common denominator between the not-quite-Tome of Wisdom and the Witch Cult Gospels possibly being that they are made at least partially from a body part or body fluid of hers much like her tea in the tea parties.
For Arcs 1, 2, 3 and 4, Subaru (and Emilia in Arc 4, which is the Sanctuary arc) was put through very specific ordeals that developed his character in a particular way, and this character development with his desire for as few casualties possible from Arc 4, the arc that pushed him to be as greedy as possible, culminated in his decision to make the speech that inspired the Priestella citizens in Arc 5.
Now as for more on why I believe there’s a grand plan to keep the world on a particular path, we know in Episode 17 that someone ordered the White Whale to leave Subaru alone, and given the Gluttony faction likely had specific instructions to not let anyone interfere with Petelgeuse’s Ordeal to Emilia, which is why Otto was attacked but managed to send his dragon carriage back to Subaru, the most likely person to have saved Subaru at that point would be Pandora since although Lye could’ve done it, I don’t see him directly opposing the Gluttony faction’s purpose for being there. Pandora’s goal may have been to teach Subaru about the White Whale’s Fog of Elimination and set him up for From Zero by having him be in complete despair after inadvertently getting Emilia killed.
As for why I believe the info on the whereabouts of the Sin Archbishop of Gluttony was leaked to Anastasia’s camp or merchant information network, we know from Arc 3 that the knights ignored Subaru’s warning about the Witch Cult attacking since they get a lot of false alarms that conditioned them to be skeptical. So it begs the question of why this info specifically made it to Anastasia’s ears and why she actually entertained it being true when it’s usually the case that no one has any info on the cult, and I believe it was to gather the Royal Selection candidates at Priestella in preparation for Subaru’s miraculous feat of making a plan to defeat/drive off four Sin Archbishops since there’s no reason for the Witch Cult to lure people to the city to defeat the cult. Priscilla may or may not have been leaked info by the same source that Anastasia got the info from, but I personally believe it’s likely as I don’t understand why Anastasia’s merchant network would go against her wishes to not let Priscilla know about her planned meeting.
Given we know from Season 3 that Witch cultists are very loyal to their Gospel with how Regulus specifically implied to Subaru that he should be grateful he adhered to his Gospel in not slaughtering a whole bunch of people en masse and how Anastasia implied that Capella follows her Gospel’s instructions to a tee even if Capella pushed back against describing it that way, the Witch Cult is known to follow their Gospels devotedly. Therefore, I put it out there that all the Royal Selection candidates were specifically gathered in Priestella for very specific things to be achieved in the story, such as Regulus’s death, Crusch being infected by black dragon blood, Subaru being infected by black dragon blood, Garfiel’s mom’s husband being turned into a black dragon, Otto restoring Roswaal’s not-quite-Tome of Wisdom, Emilia acquiring a crystal that could bring back Puck, Sirius being captured by Priscilla, Joshua’s name and memories being eaten, Julius’s name being eaten, and so on. Cultists wouldn’t question why they are bringing their enemies to Priestella as they have complete faith in their Gospels.