So, regarding this title on a new question "What is the biblical basis to prove the perpetual virginity of Mary?". The question doesn't matter here, I just always wondered where the vocabulary / thinking of "proving" something from the Bible comes from. I have often encountered this mindset, but can't take it seriously because the next guy you talk to will "prove" something different. Is this a mindset that pops up during the reformation? Maybe later during evangelical reawakenings?

Or is it a mindset that can be found earlier than the reformation? IIRC The NT also talks about "proving" Jesus being the Christ from the OT, but does this mindset persist in the first millenium of christian history? It seems people also relief a lot on philosophy to "prove" and/or describe christian theology.

@kutschkem I think "prove" might be a bit strong in that question, but anyone who holds to Sola Scriptura is likely to be skeptical of extraordinary claims that lack Biblical support. At the very least, I think such a person would argue that belief in such claims cannot be theologically important absent such support.

More generally, Sola Scriptura is essentially a blanket rejection of RCCs claims that "traditions" have any theological importance, whereas the RCC places tradition on an equal or even greater footing with the Bible. In fact, this is one of the main Protestant objections with the RCC; that the latter deems the Magisterium as having authority over scripture. This would seem to be exactly what Galatians 1:8 warns against.

@Matthew yet miracles (extraordinary claims) that occur today are accepted without specific mention in the Bible by evangelical adherents of sola scriptura… interesting

@LukeHill Really? I'd be skeptical of any claimed modern miracle. Skepticism is not the same as automatic rejection. The Bible says Jesus had "brothers". It implies that Joseph "knew her". Can those be explained away? Sure. Does that "prove" that Mary was a perpetual virgin? I don't believe so. Does it matter? I don't believe so.

In any case, my comments weren't intended to be on the Perpetual Virginity specifically, but rather an attempt to address kutschkem's questions with respect to why someone would want to "prove" something (which, again, I understood to not be referring to the Perpetual Virginity specifically) using the Bible.

Put more simply, the Bible (according to Protestants) is authoritative, everything else is not. Therefore, any claim which cannot be Biblically supported may or may not be true. Moreover, any claim which cannot be Biblically supported is probably not a matter of Salvation.