reformers did NOT believe that the "perspicacity of Scripture" meant that every layman could interpret Scripture privately and come to his own private result.
They believed that"not every passage is equally clear, nor EQUALLY CLEAR TO ALL"(westminster confession, e.g.). If that was true, there would be no need of men with the GIFT OF TEACHING, whether priests, popes, pastors, or laypersons, to teach the body of the Church.
Calvin, for example, had very high regard for the church fathers, esp. Jerome, Benedict, Bernard, Ambrose, Pope Gregory the Great, etc. He quotes them constantly.
But he didn't fail to point out where they were in error. The NT clearly records Peter being in error, after Christ's ascension. So much for papal infallibility.
The fracture brought about by the protestant reformation is not just a phenomenon that can be attributed to "sola scriptura".
The Roman Church was in serious error, serious corruption. The early magisterial reformers wanted reformation and unity with a reformed Roman church. This goal gradually slipped away more and more as time went on. It is still the goal. God will unify His church, with our without our help, in due time, because Christ prayed for the Father to do so in the high priestly prayer, and Christ did not ask for something the Father would not grant.
The cascade of fractures since the reformation are as much a result of other enlightenment dynamics and cultural/political errors which the Church will, I am confident, overcome in the future. For example, in the U.S., there is really no reason the orthodox, Bible-believing Reformed denominations should not unite into a single denomination.
They do this, because the pluralism of America allowed them to bring their faith with them, and to keep ethnic allegiance to their old national church: for example, Scottish Presbyterian, Dutch reformed, German reformed, French reformed, etc. The problem here is one of the proper relationship between church and state. In the older view, Calvin's view, the King had the right and obligation to FORCE church factions to call an ecumenical council to unify the church. Just like Constantine did.
America has allowed The presbyterians changed their view of church and state when they issued the AMERICAN wesminster confession around the time of the U.S. founding. This was a toxic compromise.
The lesson is: freedom of religion does not work for the Christian church. Some type of theocracy is necessary. The American system is poison.
There is no safe equation, whether a protestant confession, Papal infallibility, or Orthodox apostolic succession, which will provide some sort of "scientific mechanism" to lean on in order to find "infallible interpretation." It is an ongoing, living battle, waged by all of us as members of Christ's body, to interpret truth and error every day we are alive. Jesus said the Holy Spirit will "lead us into all truth" when He comes.
"And there must be divisions among you, so that it may be evident, those who are approved." -The apostle Paul.
However, if you listen to protestants who think "all truth" was done and finished with the writing of John's Revelation, then…no. Likewise if they think truth was finalized with a particular protestant confession or catechism. All church documents, where they are true and right, are simply further steps in our growth.
The Holy Spirit is STILL leading all of us in Christ's body into further truth every day. Even right here on this board.
We have infallible council statements on the Trinity. But not yet on sexuality or technology. The church fathers didn't foresee a need for those statements. The Holy Spirit will lead His church to make those statements in the future. We just have to take a long view.
He wants us to rely on HIM, not on the mere text itself, and not on any other "equation" or doctrine of infallibility, which kills and freezes truth in a particular state.
But it requires more faith to rely on the Holy Spirit to find HIS infallible will and infallible truth every day. And to repent and change when we are in error and we contradict.
Usually an option which requires more faith is the right option.
The WORD is LIVING AND ACTIVE.