If it’s wrong for Protestants to think that Calvin and Luther were simply reiterating what Paul and Peter taught, isn’t it also wrong for Roman Catholics to think that Trent was a doctrinal glimmer in the eye of the early church fathers? Merely waving the wand of doctrinal development won’t help you think historically, or understand that history is always moving, never static. And if history is fluid — which it is, as I, a licensed historian, can assure you — then what happened in the sixteenth century was not inevitable.
The way to look at it is that Luther and Calvin were in the mix of theological reflection that was going on for well over five hundred years and the Council of Trent decided to go one way and not the other. And if that is true, then Roman Catholicism as we know it (minus — ahem — Vatican I and Vatican II) started in the 1540s as much as Lutheranism started in the 1530s and Reformed Protestantism in the 1540s.
For support I appeal to Richard Muller:
The understanding of “catholic” and “schismatic” thought in the sixteenth century must be revised away from the modern denominational approach that, on the side of historians of the Roman Church, has all too willingly denied patristic and medieval roots to the Reformation and that, on the other side of older generations of Protestant historians, has tended to view the Middle Ages as harboring but few forerunners of the Reformation. The Reformers did not view themselves as schismatic; rather, they understood themselves as representative thinkers of the Catholic church. Nor can they be seen as radicals who allowed only the Bible as their foundation to the exclusion of tradition: their approach, as easily documented from their citations, was to use scripture as their ultimate norm and tradition as a subordinate, albeit fallible, support. This approach to the relation of scripture and tradition is, of course, contrary to the views of the Council of Trent, but it is surprisingly like the position of Thomas Aquinas and a great number of other major medieval thinkers. The Protestant use of patristic and medieval sources, moreover, became more explicit in the later generations of the Reformation; the nature of that reception should be a significant element of a revised historiography. (from Seeing Things Their Way)
Historians may not save us, but they can help.