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Let's review....
Let's say we have two Christians, Bob and Fred (replace those names with RCC or EO or LDS or WELS or Josiah or whatever, if you like). One holds to position "A" - stressing such as dogma, and noting that he's consistent in "A". Fred holds to position "B" - stressing such as dogma, and noting that he's consistent with position "B".
Now, I agree with the Orthodox here that if truth is moot, then it's moot as to whether Bob or Fred (or both or neither) are correct. In the words of Pontius Pilate, "what is truth?" Thus, since it jsut does't matter what is said or taught about Christ or our faith - it just doesn't matter who (if either) is correct. "Whatever...." can be the attitude. I understand.
But IF one holds that truth and falsehood matter in Christianity, that such is even knowable and discernable, that we are to embrace truth and reject error - THEN we have an assignment. It needs to be determined, to some extent, if Fred and/or Bob is correct. That is called "norming."
Now ONE of the issues in norming is the embrace of WHAT will serve as the standard, the "canon" (measuring stick) or "rule" (straight edge) or "norma normans" as it is called in epistemology. WHAT will we use? In the Rule of Law, the law is used. In my field, physics, we use two things: repeatable, experimental laborative evidence and mathematics. If I'm building a wall and want it a certain highth, I might use a tape measure. This is the rule or canon or norma normans. Some call it the standard or plumbline.
In Theology, two rules are commonly used. In the RCC and LDS, there is The Three Legged Stool: the views of self as determined by self (the RCC calls this "Tradition" and the LDS calls this "Second Testimony" - although never is confined to such) PLUS EQUALLY the Scripture in the heart of self as self understands and determines such PLUS EQUALLY the rulings, decisions, arbitrations, itnerpretations of the denomination's leadership (Magisterium, Council of Twelve). These three EQUALLY and INSEPARATELY so that what one says, the others MUST teach also so as to be in comfority. This is sometimes called "Sola Ecclesia" but often it's just known by one of the legs, "Tradition" (both the RCC and LDS teach that actually, Scripture and Denomination leadership are aspects of Tradition). The alternative is Sola Scriptura. In this case, the rule if not self but something OUTSIDE and ABOVE self, to which ALL are equally accountable - including each's own views, interpretations, etc.
Now, lets apply these to our example:
Bob holds to "A". Bob insists that the rule he'll permit is the views of Bob (which he might call "Tradition" - but it's BOB'S tradition, BOB'S views), the Scripture as BOB understands them, and the determination of BOB. So, Bob holds "A" up to the light of his own views (which includes "A" of course), his own understanding of Scripture (which he has predetermined MUST teach "A" since Scripture must confirm to Bob's views) and the determinations, rulings, understandings and interpretations of Bob. Is it likely that Bob will find that "A" measures up with his canon (measuring stick)? Frankly, it's pretty hard for it not to! But, on examination, this actually is not norming at all. THAT has been entirely evaded. What has happened is that Bob simply is showing that Bob agrees with Bob (and Fred doesn't). It has nothing to do with norming, it simply as to do with affirming that self agrees with self.
Now, let's say the Bob and Fred subject both "A" and "B" to the light of Scripture. Ah, neither Bob or Fred can have any influence on Scripture, it is not THEMSELVES but outside and above themselves. If Scripture is accepted as normative (a sound measure of what is right), then THAT becomes the "measuring stick" (canon) for the evaluation of such, for BOTH "A" and "B", for Bob AND Fred. Now we have some means for getting past the "he says, he says" and the "I agree with me.... I agree with me" that Sola Ecclesia employs.
Now, I agree, this DOES require the COMMON embrace of a COMMON canon (kinda the point). Yes, it does. Which is why it is a PRAXIS. It says this is the WAY we'll do this, this is WHAT we (WE!) will embrace as the canon. Here's where the wisdom of Sola Scriptura is apparent to me. Because the ONLY ONE ON THE PLANET that affirms that all that Bob says is correct is (at most) Bob! And the ONLY one of the planet that affirms that all Fred says is correct is (at most) Fred! Embracing each's tradition gets us nowhere. BUT both Fred and Bob (and indeed virtually all 2.2 billion Christians today and countless Christians now passed) affirm that what GOD says in His Scripture is correct. In fact, the embrace of that (and yes, the embrace of 66 books so defining) is one of the oldest, most ecumenical, strongest points of consensus in all of Christianity. Not just Fred and Bob accept that God is correct in His Scripture - but virtually every other Christian does, too! This is is STARK contrast to the tradition of the 50,000 denominations of the world (including the EO). AND, it's not just a perfect circle of self-authentication ("Hey, I alone agree with I alone!") but actually some way to break through that. Lutherans shouting, "Hey, we agree with ourselves!" isn't too convincing to you, is it? I wonder why you think others should be convinced by the same argument?
Let's say you are driving down the road at 100 MPH, down the middle of the road. Why, because according to you, driving at 100 MPH down the middle of the road is correct. Jim is driving 35 MPH on the left hand side of the road. Why, because according to Jim, that's what is right. Ah, suddenly the need for the Rule of Law comes into view. Something normative, canonical for BOTH you and Jim, to which you are both accountable. Could that be the written laws of driving? Could it include that nice, big, square white sign with black numbers that says: MAX 50 MPH? Could it include a law that says we'll normally drive on the right hand side of the road in the USA? Well, seems better to ME than everyone (EO, LDS, LCMS, UMC, RCC, Billy Graham, Josiah, you....) all looking to their OWN views on the matter, proclaiming such infallible/unaccountable - and then condemning everyone else for getting in their way (or calling them apostate, heretics, satanic, or whatever). The Rule of Scripture, like the Rule of Law, subjects ALL to the same canon respected and accepted by all.
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