If your new books were reviewed by the Catholic Church, determined to be the authentic Word of God, and added to the Bible, they would become Catholic canon.
Or, you could pull a Joseph Smith and just start a new religion with the Bible/Catholicism as your base, but with whatever nonsense you want to make up in addition to it. Mormonism somehow still has followers, so I think you could be pretty successful.
How would they know it is the "Word of God"?
The bible has been rewritten a lot already
The current ones not even in chronological order and people follow it
Most religious people, much less the irreligious, do not read their scriptures.
No one created a religion and won its following by writing a book.
In the real world the task of creating a religion typically involves a mixture of sales and warfare.
If you want to invent a religion, your best chances are putting together a good group of sales people and warlords and militia men. You need a mythical narrative sure but often you can make this up as you go along at your situational convenience (e.g. Islam).
You kind of have to convince people somehow to do it.
They don't just write a book and say follow me. They preach and try to prove themselves through miracles or use their character and make promises.Not really there's people constantly people saying they speak the word of God and create their own holy books etc... So a decent amount of people in anything are pretty impressionable
For me to take the person serious he has to prove he's really speaking for GOD and that what he says is the truth
In the real world the task of creating a religion typically involves a mixture of sales and warfare.
If you want to invent a religion, your best chances are putting together a good group of sales people and warlords and militia men. You need a mythical narrative sure but often you can make this up as you go along at your situational convenience (e.g. Islam).