The fact is sola scriptura fails for a variety of reasons.
First let us all aknowledge that the sacred scripture is not being diminished by these claims. However, it is important (if not vital) to put scripture into proper perspective.
One, if a protestant (or any Christian for that matter) believes in scripture alone, then you need to believe the Church is the pillar of all truth. It says this in 1st Timothy 3:15.
It actually affirms the role of the church in relation to Gods Law in Acts. It was determined that the NEW authority had the power to change doctrine. If it was "SCRIPTURE ALONE" then the early Church would not have had the AUTHORITY to change the Law of God. Mainly, circumcision. This also goes for a wide variety of the Mosaic Law.
All of the Mosaic Law is SCRIPTURE. Therefore if it was ONLY SCRIPTURE, then the CHURCH would not have had the AUTHORITY to change this. They did, and it was affirmed IN SCRIPTURE. The ironies here are astounding.
The sola scriptura claims cannot be true. The Church is the authority. Is this not true? Then by what authority did the Church change scriptural LAW?
The notion that the church has stopped growing, or that there were no issues to be ruled on, or that the church no longer had authority to determine doctrine upon the deaths of the 12 apostles is beyond ridiculous. That would have to be the claim. It is almost as though the Holy Spirit no longer inspired anyone for close to 2000 years.
Not to mention that fact that we know for a fact that Christians did not carry around pocket bibles. Most Christians were illiterate for close to 1600+ years. We know the canon was not really put together until 382AD. What did the early Christians go by for the first 300 or 400 years? SHoulder shrugs are not answers. Cause the answer is they went by the oral traditions. Paul IN SCRIPTURE says to hold fast to the traditions as we have passed them on to you.
There are so many other points to show that God or the Church will not be limited to JUST the writings of Paul.Why? Cause the same Holy Spirit that guided Paul is the same Holy Spirit that guides the Church today.
Do we think Peter only wrote 2 letters? Is it wrong for me to presume Peter wrote a lot more than 2? Is it wrong for me to presume that the Holy Spirit guided him in those letters too?
The notion of sola scriptura is another claim that does not hold up to scrutiny. At best, it shows how narcissistic humans can still be. Like when we thought the entire universe revolved around us. Imagine that.