That is the whole point. Do we make Scripture the highest authority or the Roman Church? Protestants say the Scripture, and Roman Catholics say the Church. I seem to remember that was an important part of the Reformation.
Yes, it is an important part of salvation. Christ said He would build His Church, and He gave us people not a book. The book testifies of the Church
Christ said so directly to the Pharisees in John 5. You search the scriptures and think you have eternal life in them, but the scriptures testify of me and you don’t believe. That is as the Old Testament, which was a shadow of things to come.
The New Testament speaks of the Church that Christ built. She is still here, and people don’t believe. Why was the book written? So anyone can claim plain reading and become stubborn in error? The Holy Spirit was promised to the Church, not the book.
Yes it is a contention of the reformation, but contention does not equal truth. The plain reading of scripture shows that Christ built a Church, the Holy Spirit was promised to the Church, the Apostles were sealed with tongues of fire on Pentecost. The book did not receive the same benefits.
Our human mind does not like it, we think we know better and can do better, but is not self sufficiency the original lie of Satan? “You shall be as gods knowing good and evil”?
Is not humility the Christian path? Not my will but thine be done?
The choice seems pretty clear but not pleasant.
Humble and deny yourself and take up your cross to follow Jesus, or exalt yourself and start your own church or join one that another man or woman has started.
Me and my house will follow the Lord.