This has all pretty much already been said on here at some point, but this is what I’ve learned:
(and I will consider myself here as a non-C since I’ve been questioning my faith for a few years…)
I would have to say ‘The Bible’, of course, and I doubt there is a Catholic here who’d dare to say that the Catholic Church has a teaching that isn’t somehow connected to scripture (though not explicity).
For you and I (speaking generally) who have had familiarity with scripture and theology and apologetics (even just a bit, from here, reading, tv, etc…) it is easy to take for granted what we have actually been taught and how that influences our understanding/personal interpretation. It is quite impossible to read scripture totally objectively after having been somewhat “indoctrinated” by these influences.
The question of extra-bilical authority is a very valid one if you consider someone who has had no exposure whatsoever to theological dialogue. Like the Ethiopian enuch, there must be some man to guide. It is obvious from the innumerable people claiming to have the authority to guide, and the innumerable contradictions amongst their teachings, that they cannot all be interpreting them correctly. Also, no matter how intelligent and sincere we may be, we all have our own personal handicaps that influence some bias in how we interpret things - iow we have a tendancy to make the scriptures mean what we want them to - and I dare say it is probably impossible for us not to w/out divine guidance. Yes, all us believers have the indwelling Holy Spirit, but do we all “speak the same things” and are we all “of the same mind”? The Holy Spirit doesn’t contradict himself.
It’s tempting to say to yourself, “but we should study and with study should come an understanding of the true interpretation. I believe I (or my Lutheran, JW, Pentacostal, etc… pastor) interpret the scriptures this way b/c I’ve (they’ve) studied them so well over the years and I can see this interpretation so well…” But what about some simpleton or under-priveleged person who doesn’t have the resources or capacity to study them or fairly judge his “guide”/church/pastor/etc…??? Is God excluding them from the truth? Does the truth not matter?
Keep in mind the many ways in which man has grossly distorted the Word of God in the past (and present even) and the results of that…
We need a guide, or we have chaos, and that is obvious if you look around at the ridiculous number of denominations out there.
Authority matters. Someone may think it doesn’t b/c they believe they are well-adjusted, smart, inspired, well-intentioned, etc…, but no matter b/c in the end it is sheer pride that brings one to conclude that they have the correct understanding of scripture. For every smart, well-intentioned, learned, inspired person out there with their own interpretation there is another, equally, smart, well-intentioned, learned, inspired person with a contradicting interpretation. And you can’t say “well, how do I know those other people aren’t well-intentioned, or have some other handicap preventing them from fully understanding?” b/c in the end we all have something that will prevent us (unknowingly) from getting it right. One’s sincerity isn’t going to ensure infallibility.
Just like with civil law, we need an authority. Can’t lay out the Constitution and leave no interpreter/guide.
That said, I think authority is the number one issue preventing non-C’s from being Catholic, and even though I see the point, I’m still not ready to be reconciled with the CC. I still can’t see past some of those “obvious scripture contradictions” that I, admittedly, interpret for myself. Maybe I’m just too proud to admit that they may not be contradictions. I think it is more likely that, b/c they seem so obvious to me, I am scared to ignore them or accept a seemingly valid Catholic defense for them. It’s too easy to accuse yourself of following man above God. It’s more comfortable to say “I believed what I clearly saw in God’s Word. It HAS to be from God!” The words may be, but perhaps not the interpretation…