6monkey9 Godot is a game engine, not an ebook reader. It's not optimized for rendering large amounts of text, especially not rich text.
Also, the Bible consists of many separate books and chapters that can be processed separately. Working with a single big string that stores all of it is completely unnecessary and very impractical for myriad of reasons.
And note that this thread was about splitting the text into multiple boxes that are displayed at the same time. If you only have one box (as ebook readers do) - you don't need any of this.