Nathan,
Perhaps some American "Evangelical" preacher (lacking education in this matter) conveyed to YOU that YOU should not read certain books which you discovered many Orthodox, Catholic, Anglican and Lutheran Christians have and still read. And this upsets you (you have an enormous passion about this!!!!) Brother, take that out on your (perhaps uneducated) "Evangelical" preacher. CHRISTIANITY has never said that. PROTESTANTISM has never said that. No pan-Christian or pan-Protestant declaration of any Ruling Body of such ever said that. Your preacher might, however. Since that seems to REALLY bother you, go to a different church. Consider an Anglican or Lutheran one - or perhaps a Catholic or Orthodox one.
Read this (although it may burst your American Evangelical teachings)....
What WE 2.2 billion Christians today HAVE in this regard is a product of a consensus.... of TRADITION.... not some pan-Christian authoritative meeting of some Ruling Body with a date and place and decision. And this consensus has NEVER, not EVER, been absolute or perfect or universal.... although more so with the NT than OT. It's pretty solid over (by our numbering) 66.... less so for an addition half to full dozen, less so for perhaps a dozen more.
AND EVEN WITHIN that consensus, there has been a RANGE in their acceptance, their "canonicity" (the word we use for this in theology) - not all "Scripture" was view EQUALLY until after the Reformation (and even then, only in some denominations). Not all "canonical" Scripture has been seen as EQUALLY "canonical." Christians often placed the NT over the OT, the OT being canonical but less so than the NT. The 39 OT ones over any DEUTERO (look up the word!) ones.... some NT books were considered less canonical than others (Revelation, Hebrews for example - often not even included in lectionaries). Luther and Calvin both felt for a few years that Romans and James were in conflict (both eventually changed their minds) BUT Romans is more canonical than James, they both argued. A lot of this disappeared after the Reformation but the Anglican Church officially embraced it with the distinction it made for the pre-Christ books - the 39 Articles did NOT remove anything from the BIBLE (as you note) but they DO insist some are only DUETERO canonical while others are fully canonical.
Sorry my modern American Evangelical brother.... it's not as "neat" or "objective" as your Sunday School teacher taught you. And I know it hurts American Evangelicals to admit that floppy book with "BIBLE" on the cover is a product of TRADITION (and fairly loose one at that) NOT the result of God sending a memo down from heaven or Scripture including a "Table of Contents" or even the Church speaking in some definitive, ecumenical way. Nope. Not even close. OVER TIME, over a period of more than 1500 years - ONE THOUSAND, FIVE HUNDRED YEARS - a consensus developed, one that is NOT perfect, NOT universal, not absolute. I know this disturbs 21st Century American "Evangelicals" who were told that Tradition is a bad thing.... who were taught God sent a memo in 33 AD with a list of what books are Scripture on it. But they were just taught wrong. Tradition COUNTS - even if it RARELY is perfect or universal.
Sorry to burst your bubble. There's a LOT of false concepts in modern American "Evangelicalism."
I understand how you perhaps have come to perhaps learn that your Evangelical church is wrong about this. It's likely wrong about a bunch of stuff. But don't aim your anger at all Christianity or all Protestantism just beause perhaps your preacher or teachers are ignorant. Nearly all Christianity.... for 2000 years.... is perfectly okay with you reading 2 Maccabees and/or Judith. They may not affirm any tradition of them being EQUALLY canonical, having EQUAL canonicity with same the Epistle to the Romans but that doesn't mean there's some law that they cannot be in a book with "BIBLE" on the cover or there's some binding law passed by some Ruling Body of All Protestantism (you insist on knowing the DATE and PLACE of a meeting that never happened!) that they cannot be read or used. Go ahead.... read them, use them - just as Luther and the Anglican Church so encouraged. Have studies on them as we do in both the Anglican and Lutheran Churches (but it seems not Catholic). BUT when you insist that some Ruling Body of All Christianity declared them to be fully canonical, there you are just wrong.... equally wrong with perhaps your preacher, simply not knowing history.
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