Here is the fundamental difference that is irreconcilable. You will trust those who came later. I will trust the source they all should have measured everything by, SCRIPTURE.
Calvin, Luther, et al came latter. The church fathers were there.
Further the only reason protestants knew which books to traanslate (which the accomplished poorly) is because of these same church fathers. Without those church fathers protestants wouldn’t know that the Gospel of Judas was gnostic. They’d have to accept the Protevangelion of James as scripture.
The irreconcilable difference is trusting a 15th century man over the Holy Spirit.
Where is that sentiment contained in SCRIPTURE? And I don't mean a quote that can by tortured into that interpretation, but the exact quote. Doesn't SCRIPTURE declare that it does not and could not contain all that Jesus said or did?