What is the Biblical Basis for Sola Scriptura? was closed as a duplicate of What is the basis of my fractured understanding of "Sola Scriptura"? even though that one isn't actually about sola scriptura. Meanwhile, that's what this hard-to-find and sort of unclear question seems to be asking: Why is the Bible a foundation of theological evidence?
My proposal: we reopen the first question and then close the last as a duplicate of the first.
Or better yet, since the first question is poorly asked, long-closed, and by an inactive user, it could stay closed and a new question could be asked.