How do we know that the Bible has the authority of no other book? Let’s allow it to speak for itself.

“Sola Scriptura” was the rallying cry of the Protestant Reformation. For centuries the Roman Catholic Church had made its traditions superior in authority to the Bible. This resulted in many practices that were in fact contradictory to the Bible.” (gotquestions)

What does the Bible have to say about its authority?

“The primary Catholic argument against sola scriptura is that the Bible does not explicitly teach sola scriptura. Catholics argue that the Bible nowhere states that it is the only authoritative guide for faith and practice. However, this is only true in the shallowest sense.

“The principle is strongly indicated by verses such as Acts 17:11, which commends the Bereans for testing doctrine—taught by an apostle, no less—to the written Word.” (gotquestions)

Acts 17:11 NIV
[11] “Now the Berean Jews were of more noble character than those in Thessalonica, for they received the message with great eagerness and examined the Scriptures every day to see if what Paul said was true.”

Paul was obviously referring to the Tanach, the writings we call the Old Testament, which was already in existence and authoritative for the early church since the church recognised the gospel of Jesus as the continuation and fulfilment of the Old Testament Scriptures.

“Sola scriptura is all-but-explicitly indicated in 1 Corinthians 4:6, where Paul warns not to “go beyond what is written.” (gotquestions)

1 Corinthians 4:6 NIV
[6] “Now, brothers and sisters, I have applied these things to myself and Apollos for your benefit, so that you may learn from us the meaning of the saying, “Do not go beyond what is written.” Then you will not be puffed up in being a follower of one of us over against the other.”

Since the early church recognised the authority of the Tanach, there was no place for competition between church leaders. They were bound by what was written in the Scriptures.

“Jesus Himself criticized those who allowed traditions to override the explicit commands of God in Mark 7:6–9.” (gotquestions)

Mark 7:6-8 NIV
[6] He replied, “Isaiah was right when he prophesied about you hypocrites; as it is written: “ ‘These people honor me with their lips, but their hearts are far from me. [7]  They worship me in vain; their teachings are merely human rules.’ [8]  You have let go of the commands of God and are holding on to human traditions.”

There is multiple evidence in the gospel records that Jesus based His entire life and teachings on the Old Testament Scriptures. His disclosure to the two disciples on the Road to Emmaus after His resurrection reveal the foundation  of His earthly life and death.

Luke 24:25, 27 NIV
[25] “He said to them, “How foolish you are, and how slow to believe all that the prophets have spoken!
[27] And beginning with Moses and all the Prophets, he explained to them what was said in all the Scriptures concerning himself.”

The article on “Sola Scriptura”, found in www.gotquestions.com concludes with this argument.

“We know that the Bible is the Word of God. The Bible declares itself to be God-breathed, inerrant, and authoritative. We also know that God does not change His mind or contradict Himself. So, while the Bible itself may not explicitly argue for sola scriptura, it most definitely does not allow for traditions that contradict its message. Sola scriptura is not as much of an argument against tradition as it is an argument against unbiblical, extra-biblical and/or anti-biblical doctrines. The only way to know for sure what God expects of us is to stay true to what we know He has revealed—the Bible. We can know, beyond the shadow of any doubt, that Scripture is true, authoritative, and reliable. The same cannot be said of tradition.”

Where tradition clashes with or contradicts Scripture, our only safe position is to trust the Bible to be what it claims to be, the authoritative Word of God.

“The Word of God is the ultimate and only infallible authority for the Christian faith. Traditions are valid only when they conform with Scripture. Traditions that contradict the Bible are not of God and are not a valid aspect of the Christian faith. Sola scriptura is the only way to avoid subjectivity and keep personal opinion from taking priority over the teachings of the Bible. The essence of sola scriptura is basing one’s spiritual life on the Bible alone and rejecting any tradition or teaching that is not in full agreement with the Bible.  2 Timothy 2:15 declares, “Do your best to present yourself to God as one approved, a workman who does not need to be ashamed and who correctly handles the word of truth.”

Paul assured his protege, young Timothy,

2 Timothy 3:16-17 NIV
[16] “All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness, [17] so that the servant of God may be thoroughly equipped for every good work.”

Like Paul, we can have every confidence in the authority of the Bible since it testifies to and proves the truth of its claim.