Some Christians want to limit debate to the Bible, but the Bible tells us just the opposite-
“I praise you because you remember me in everything and hold fast to the traditions, just as I handed them on to you.” (1 Cor. 11:2).
“Take as your norm the sound words that you heard from me, in the faith and love that are in Christ Jesus. Guard this rich trust with the help of the holy Spirit that dwells within us." (2 Tim. 1:13-14).
“Therefore, brothers, stand firm and hold fast to the traditions that you were taught, either by an oral statement or by a letter of ours." (2 Thess. 2:15)
" So you, my child, be strong in the grace that is in Christ Jesus. And what you heard from me through many witnesses entrust to faithful people who will have the ability to teach others as well." (2 Tim. 2:1-2).
"‘Although I have much to write to you, I do not intend to use paper and ink. Instead, I hope to visit you and to speak face to face so that our joy may be complete." (2 John 12).
“There are also many other things that Jesus did, but if these were to be described individually, I do not think the whole world would contain the books that would be written. (John 21:25)
The Bible itself never makes that claim that it is all you need - this belief is a tradition of man.
Some may point to Timothy - “But as for you, continue in what you have learned and have become convinced of, because you know those from whom you learned it, and how from infancy you have known the Holy Scriptures, which are able to make you wise for salvation through faith in Christ Jesus. All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness, so that the man of God may be thoroughly equipped for every good work. (2 Timothy 3:14-17) However, the Scripture that Timothy studied in his infancy was the Old Testament. Paul said nothing about the New Testament here, much of which was not yet written at the time. And equipping for every good work falls short of everything needed for salvation.
See if you can answer these two questions from Scripture –
1. Where does the Bible say that it contains all you need for salvation?
2. Where did the table of contents for the Bible (Old or New) come from?
If Martin Luther had his way, you would have a Bible without the letter to James. “You see that a person is justified by what he does and not by faith alone.” James 2:24 This didn’t agree with Luther’s interpretation of salvation by faith alone, so he wanted to take that one out as well. (“Tell them Martin Luther says it is so”).
Jesus wanted us to be one. “I appeal to you, brothers, in the name of our Lord Jesus Christ, that all of you agree with one another so that there may be no divisions among you and that you may be perfectly united in mind and thought. My brothers, some from Chloe's household have informed me that there are quarrels among you. What I mean is this: One of you says, “I follow Paul”; another, “I follow Apollos”; another, “I follow Cephas”; still another, “I follow Christ.” Is Christ divided? Was Paul crucified for you? Were you baptized into the name of Paul? 1 Cor 1:10-13 We cannot be one if everyone brings his own version of the Truth. "First of all you must understand this, that no prophecy of Scripture is a matter of one’s own interpretation, because no prophecy ever came by the impulse of man, but men moved by the Holy Spirit spoke from God" (2 Peter 1:20-21). Christ was not stupid, and He knew He had to establish a visible Church with authority to keep men from twisting His words. He did just that. The Catholic Church has existed for nearly 2,000 years. No other church can make that claim. The Bible wasn’t widely available for the first 1,500 years of Christianity. What did the early Christians do? They belonged to the Catholic Church.
By the way, I am Catholic and I do quote what Martin Luther said about the meaning of the word “IS”- "Who, but the devil, hath granted such a license of wresting the words of the holy Scripture? Who ever read in the Scriptures, that my body is the same as the sign of my body? or, that is is the same as it signifies? What language in the world ever spoke so? It is only then the devil, that imposeth upon us by these fanatical men .... Not one of the Fathers, though so numerous, ever spoke as the Sacramentarians: not one of them ever said, It is only bread and wine; or, the body and blood of Christ is not there present. Surely it is not credible, nor possible, since they often speak, and repeat their sentiments, that they should never (if they thought so) not so much as once, say, or let slip these words: It is bread only; or the body of Christ is not there, especially it being of great importance, that men not be deceived. Certainly in so many Fathers, and in so many writings, the negative might at least be found in one of them, had they thought the body and blood of Christ were not really present: but they are all of them unanimous."
Martin Luther, tom. vii. Edit. Wittemb. p. 391 (from post 86)
Notice how Luther refers to the writings of the Fathers?
I enjoy these discussions to broaden and deepen my understanding of what Christ wanted us to do. But I believe John when he tells us “There are also many other things that Jesus did, but if these were to be described individually, I do not think the whole world would contain the books that would be written.” And certainly not just one book.