This is one that bothered me when I was a more traditionally Bible-believing Christian lo so many years ago.
From Wikipedia:
As a lad, the churches I was raised in didn’t specifically use the phrase “Sola Scriptura” but they certainly would have affirmed the doctrine described above. Indeed, one of the churches I was raised in would have gone further and would have affirmed the strengthened doctrine that:
The first version says the Bible contains everything necessary. The second version says the information contained in the Bible is not only necessary, but sufficient.
It’s the combination of necessity and sufficiency that my objection is most directly aimed at. But I’ll say something about the mere necessity condition as well.
Suppose the information contained in the Bible is sufficient for salvation.
Now suppose someone believes everything in the Bible but also believes that the information in the Bible is insufficient for salvation. Hence they believe there is additional extra-biblical information required for salvation.
Such a person, according to anyone who affirms either version of Sola Scriptura, would not be saved.
Let’s say that’s correct–that such a person isn’t saved.
Then we must (if we share certain basic assumptions common to all believers in Sola Sccriptura) conclude that the belief that the Bible is sufficient is itself necessary for Salvation.
But, by Sola Scriptura, this means that the doctrine of Biblical sufficiency for salvation is itself contained (or at least implied) in the Bible.
This, in turn, is logically equivalent to the following (together with some assumptions held in common by everyone who believes in Sola Scriptura):
“For each of the books of the Bible listed in Frylock’s NRSV (except the apocrypha–we’ll maybe say something about that in a moment) there is a version of that text–call it V(t) where t is the book of Frylock’s NRSV under consideration–such that the collection of all V(x) for each x==one of the books in Frylock’s NRSV is itself necessary and sufficient for salvation.”
Which, in plainer English, means “Genesis is part of the work necessary and sufficient for salvation, Exodus is part of the work, Leviticus is part of the work, …, Jude is part of the work, and Revelation is part of the work.”
In other words, if Sola Scriptura is true, then the Bible must define itself somewhere.
So–how does it do this? How does the Bible define itself?
This is a problem, I think, even for the weaker version of Sola Scriptura listed first above, since given the truth of Sola Scriptura, it appears that Sola Scriptura is itself necessary for salvation. (Maybe not, though.)
I’m not worried about the Apocrypha, because the churches that accept them as scripture also do not affirm Sola Scriptura.
TLDR: Where in the Bible say that the books from Genesis through Revelation found in my copy of the NRSV, minus the Apocrypha, contain all the information you need for salvation?