I stick with quoting scriptures...Can you imagine a Bible that covered "everything" important to the Christian faith? It would be ten miles high and then some. http://www.catholic.com/tracts/scripture-and-tradition
Your post begs the question "what is important to the Christian faith?"
It would be ten miles high and then some.
That's a mighty big list! It reminds me of the amount of luggage the Howells brought with them for a three hour tour around the islands of Hawaii. Do you really "need" all of that stuff? Is it all that important? Can you imagine a list of "everything important" to the faith, that's still concise enough to fit into a single Bible?
"Catholics, on the other hand, recognize that the Bible does not endorse this view and that, in fact, it is repudiated in Scripture. The true "rule of faith"as expressed in the Bible itselfis Scripture plus apostolic tradition, as manifested in the living teaching authority of the Catholic Church, to which were entrusted the oral teachings of Jesus and the apostles, along with the authority to interpret Scripture correctly."
But it lacks scriptural authority. It is illogical to use a statement on doctrine as the authority itself. 2 Thess. 2:15 is the reference given, but that is an Apostle telling his disciples that the revelation given to him and sated as such, either written or verbal, is to be considered authoritative doctrine. It does NOT sanction church tradition as being authoritative:
"2 Thess. 2:15 With all these things in mind, dear brothers and sisters, stand firm and keep a strong grip on the teaching we passed on to you both in person and by letter.
Mormons use this same argument that not everything God wanted us to know is in the Bible - He gave additional revelations to other apostles and prophets - like Joseph Smith. I'll stick with the admonition in Revelation 22.
That's not to say that supplemental materials aren't useful so that idioms, locations, and traditions mentioned in the Bible can be understood today. But, they are not scripture or doctrine and should not be used as such.
Other scriptures that are specific prohibitions on adding to, or taking away from the word of God are:
Deuteronomy 12:32 What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it.
Proverbs 30:5-6 Every word of God [is] pure: he [is] a shield unto them that put their trust in him. Add thou not unto his words, lest he reprove thee, and thou be found a liar.
Gal 1:8 But even if we, or an angel from heaven, should preach to you a gospel contrary to what we have preached to you, he is to be accursed!
Revelation 22:18-19 For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book: And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and [from] the things which are written in this book.