i'm still trying to figure out what this means, but there seems to be something very good here. i'm not smart enough to fully understand though because of the way this is written.
I’m not the OP, but here’s my attempt at explaining what he’s saying in less-theological terms:
“continuity of doctrine” and “preservation of the deposit of faith” have to do with the belief that the Church’s teaching authority is inspired by God. all catholics (theoretically) must believe this, and confirmed catholics profess it during their confirmation: “I believe and profess all that the holy Catholic Church believes, teaches, and proclaims to be revealed by God.”
for some people, who consider themselves traditionalists, this is taken to mean that every single idea and practice ever espoused by the roman church is unchangeable and unchanging, and any alteration is heresy.
in contrast the OP uses the term “peripheral applications” to mean “stuff that isn’t dogma [absolutely true, authoritative teaching], but rather the way we apply dogma to real-world situations”.
this thread is in response to the hullabaloo over the revision of the catechism i/r/t the death penalty - in specific he’s saying that
- by changing the official stance of the church from “the death penalty is acceptable in some situations where it’s the only way to protect people” to “the death penalty is never acceptable because it’s no longer ever necessary to protect people,”
- the pope hasn’t wrongfully altered dogma,
- he’s applying the dogmatic statement “humans are made in the image of God and have infinite value and dignity” (a teaching which cannot change) in a new way in light of modern society’s ability to keep very dangerous criminals incarcerated without endangering others.
and in a general way, OP’s saying that the “traditionalists” mentioned earlier are
- proceeding from the incorrect assumption that every application of church teaching is equally central and unchangeable, and
- either haven’t studied the way things have changed over the course of church history, or begin their study with assumption (1) and selectively read/understand church history in a biased way to validate that assumption.
hope that makes more sense (and that I’ve understood the OP correctly)! it can be tough to jump in on complex theological discussion when there are so many unfamiliar terms, so I’ve tried to lay it out more colloquially here.