Best analogy for religion I've ever heard: "A D&D game that went too far." If you've seen diehard gamers go on for hours about the minutiae of various editions of countless rulebooks, you can imagine what it's like when devout Catholics get together to talk shop.

There are subtleties to this particular pissing match that aren't immediately obvious. The Vatican is starting to rein in the Opus Dei cult-within-a-cult. After John Paul II canonized its founder in 2002 on shaky grounds, later Popes have started to think that maybe they went a little too far. Meanwhile, Opus Dei has focused on gaining more secular influence in government (https://www.theguardian.com/us-news/article/2024/jul/26/kevi...).