There is a most interesting speech by Pope Benedict XVI (then Jospeh Cardinal Ratzinger), at Pontifications. It was given July 13, 1988, in Santiago, Chile before that nation’s bishops. It is a remarkable statement regarding the living Magisterium, dogmatic truth, constructive criticism, and self-examination. It looks at the Lefebvrian Schism but it also gives some great theological insights.
So here is a couple of sentences from Early Ratzinger on the Lefebvrian Schism.
One of the basic discoveries of the theology of ecumenism is that schisms can take place only when certain truths and certain values of the Christian faith are no longer lived and loved within the Church. The truth which is marginalized becomes autonomous, remains detached from the whole of the ecclesiastical structure, and a new movement then forms itself around it.
This is an insight to be considered well. Far from saying that reforming movements are all wrong, the Holy Father shows that the undervalued truths elevated by these reforming movements become normative. When truth is removed from the context of the Church it takes on a life of its own. Take the Protestant (as opposed to the Catholic) view of Scripture. Take the Catholic Anglican view of Sacramental Validity, and liturgy. The wholeness of the faith needs to be present at all times within the right context, the Church.