Stop right there. “God’s word”
This is where Petrine authority comes in. Every Tom, Dick, and Harry does not get to offer “his”’/”her” authoritative interpretation of God’s “Word” This is the heresy of the Reformation, where we have everyone and their grandmother thinking they can crack open the pages of the Bible and offer us “their” interpretation of “God’s “word.” God’s “word” is also His unwritten words and actions.
Many of these eminent theologians are saints of the Church beginning with early Church fathers who assembled the “books” in the Bible under Petrine authority.
That's right, GOD'S word - Sacred Scripture. His revelation written down as He has done since Moses. God knows all too well the propensity of men to corrupt His truth and it's why Holy men of God spoke as they were moved by the Holy Spirit, they were written, copied, distributed and preserved. It is folly to imagine unwritten "traditions" are in any way comparable to Divine inspiration. Within a few decades after Christ ascended, His teachings and the continued revelation was being written down so that there would be a record to be used as both resource and rule of the faith. John's Revelation was the last of the New Testament books to be written.
There are first and second century writings of Christian leaders that teach and list the writings - as well as acknowledging their Divine origin - that were received by Christ's own that make up the NT and if all the manuscript copies of those books were destroyed, almost the entire NT could be reconstructed using their writings. The later councils did nothing more than confirm what was already believed by the church at large. The church was not dependent upon the decision of a council for the contents of the NT.
The ONLY "Petrine" authority was the same Apostolic authority Jesus gave to the other eleven and it was NOT something that could be handed down from an Apostle to his "successor" - ONLY Jesus anointed His Apostles. There was a handing down of the gospel truth and that was what determined if a man was speaking as from the Lord. Peter called Paul's epistles "Scripture", he didn't need to wait for a council to decide it for him three hundred years after he was martyred. Obedience was expected and those who would not were excluded from the fellowship.