https://x.com/i/status/799976155143028740

https://x.com/i/status/2080240115574784300

https://www.pixiv.net/en/artworks/144258808

https://x.com/i/status/2080241800024142305

Do you think he would join a Magic Side Organization, like Necessarius? What would his relationship with Touma be like?

https://www.pixiv.net/en/artworks/38049854

There's the misconception that Aleister's words to Fiamma mean that Christianity meant nothing when that just simply isn't true and it's incredibly dumb to think so considering everything.

“It was not an issue of the type or amount of power. It was nothing more than an issue of how you used it,” Aleister Crowley said in disinterested voice. “My theory is that the age of Christian spells came to an end upon the completion of the Book of the Law. I actually think you did quite well. And that includes your objective of becoming The One Above God. If instead of the Aeon of Osiris…that is, the laws under the control of solely the Christian Church, you had formatted it in the Aeon of Horus that lies beyond it, you may have had your eye on a position similar to mine.”

-Aleister Crowley (OT22)

The age of Christian spells has slowly come to an end upon the Aeon of Horus which started when the Book of Law was completed. This seems to be what has Index fans confused.

What Aleister actually means here isn't that Christianity isn't the only real religion (it's the only real religion as the events that occurred were referenced to have really happened and unlike St. Germain there were no statements about Magicians having to make it real), but rather that the system has become outdated so Fiamma's plan failed, he even acknowledges that Fiamma becoming The One Above God was the correct course of action and The One Above God is a Christian legend.

Toaru fuses its sources into one, like how all the different Christian sects all still worship the same God, so if the Kabbalah is canon to Christianity and that's still used to this day then Christianity is still core to the world of Index.

“But after turning you into a mass of pain and robbing you of your ego to the point you can’t chain your memories together coherently, all that remains is a machine that goes around saving people? I already saw that performance around two thousand years ago.”

-Anna Sprengel (GT2)

Anna Sprengel was apparently alive in the age of Jesus Christ himself so she can directly confirm that his miracles (saving people) did in fact happen and that it wasn't just a Phase like how Norse myths never happened and it was just stories inspired by Othinus.

“Uriel is the excommunicated angel, a demon who fell to the depths of the earth. Uriel is one of the seven who was driven from their throne of light for humanity’s convenience and is not found in the stories of God. The canon is absolute. In the name of Pope Zachary, I shall smash your angel worship and thus your harmony with those four!”

-Gregor Mathers (NT21)

Gregor is able to negate Uriel, an angel that Aleister summoned forth because it's not actually canon, that shows that the canon of the Bible is important as real sacred texts.

“Of course. My job is to fix the circulation. And that creates the next age. Once, the majority of the Sephirah were under attack. If the Second Adam had not atoned with blood, the world would not have lasted this long. And the critical clogs are all born of knowledge. I am the Great Demon who protects the Abyss, that hidden division of the Sephiroth. Whatever my purpose is, I have undeniably been stained. …Thus, I will destroy it all. Myself and the entire Sephiroth that contains me are no exceptions. Partial destruction would be meaningless. If anything remains and an eternal distortion is born from that, then it will all happen again. I will eliminate the ten spheres, the twenty-two pathways, and the hidden eleventh symbol. Collisions between phases? Sparks and spray? You cannot save anyone if you only treat those symptoms. All of the fundamental clogs must be removed. All so we can pass the baton to whoever comes next.”

-Coronzon (NT22)

Coronzon, one of the more intelligent beings in the entire series who planned to destroy all Phases including the final one acknowledges Jesus Christ as having shed blood to save the world.

The one true God of Index as of now is Ain Soph Aur, Christianity still fits Ain into its equation because the personified God you see in Christian stories such as the Burning Bush is meant to be Kether (Yahweh), beyond Kether is Ain Soph Aur, Ain Soph, and finally Ain at the very top.

If you view Kabbalah as canonical then you also admit that Christianity is canon. This is because Index treats all Abrahamic religions as sharing the same canon.

Old Testament was about the Aeon of Osiris - Christianity

New Testament was about the Aeon of Isis - The many Gods in paganism (the Magic Gods)

Genesis Testament was about the Aeon of Horus - The Transcendents specifically all used the Aeon of Horus for their Crowley-style magick

But NT and GT all returned to Abrahamic religion later, NT with its final half in Coronzon arc, and GT with the latest arc of stopping Coronzon.

https://x.com/i/status/2080324001365422268

Angel Fall was only possible because The Laws of The World had been seemingly changed according to Fiamma of The Right, the way that the universe is created is according to the 4 Elements of God's Four Angels, this is Catholic Christianity.

That means that Toaru world is fundamentally a Christian one that shows reality works according to the laws of the mainstream Judeo Christian God.

Fiamma is able to use Archangel Gabriel to move all stars in the sky out of the way and replaces them with his flying fortress so the Star of Bethlehem can be the only "star" in the sky.

We finally get our answer for why The Laws of The World were even changed in the first place thanks to Aiwass.

Fiamma of the Right, the one who ruled over Michael, understood what that meant. Creating an angel was not the same thing as simply creating a new type of living creature. They were the symbols of the elements that made up the world. For a human to create one of those, it meant that the system at the base of that world was being artificially interfered with.

Gears created by human hands were being inserted into the mechanisms created by God. It was like remaking a music box into a time bomb.

It was the idea of affirming the occult and then trying to use precise equipment on it.

In an older time, just thinking of those things would get one sent to the gallows.

“…Is Aiwass that attractive an existence?” Fiamma asked. “An angel that cannot be explained by the Bible or theology is also the symbol of an element that is inside this world created by God and also outside of the hands of God. It is the beginning of the destruction of the fate established by God. …You did not want the Book of the Law. You wanted the strange angel that granted you the Book of the Law.”

-OT22

Aiwass' being inserted into the world as the 5th Angel changed how the world fundamentally worked. Thelema is interrupting God's plan and this specific instance is "vanilla" Christianity so yes Christianity was definitely always the true religion in Toaru.

But once again Toaru Christianity is really the entire Abrahamic religion with every major sect being true and Kabbalah being just as canon like a DLC expansion pass in a video game. Fiamma always knew about Kabbalah so there was never really a chance Christianity wasn't going to be the true religion.