The Bible was inspired by God and written by men who he chose for himself and filled with the Holy Spirit so that they would compose what he desired (2 Peter 1:21). The Lord did this to reveal himself to humanity. The scriptures are the actual, genuine words that God has spoken - they are God-breathed (2 Timothy 3:16). The words of scripture are authoritative because God is the ultimate author of them, and by virtue of his very authority as creator and sustainer of all things, they bear weight in all of life for all people. 

Since it is of divine origin - being written by the Holy Spirit through the instrumentation of men - the Bible must be recognized as the very word of God. The breakdown of scripture is one aspect that points to this being true. The scriptures were written over thousands of years, and by many diverse men, as well as spread over hundreds of miles and through many sundry situations. This being the case, however, all of scripture is cohesive and has one central theme: the gracious and merciful character of God and his glory manifest in the world through a chosen people for his possession. 

Second Timothy 3:16 says, “All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness.” When the scripture speaks of being breathed out by God, this means that it is literally what God has said. In other words, it is inspired by God. The Bible attests to its inspiration, with God as the highest authority to which we can appeal. This means that all 66 books of scripture, the entire Old Testament and the entire New Testament, are inspired. Westminster Confession of Faith helps us in 1.2,3 saying,

2“Under the name of Holy Scripture, or the Word of God written, are now contained all the books of the Old and New Testament, which are these:

Of the New Testament:

The Gospels according to

Matthew

Mark

Luke

John

The Acts of the Apostles

Paul’s Epistles

To the Romans

Corinthians I.

Corinthians II.

Galatians

Ephesians

Philippians

Colossians

Thessalonians I.

Thessalonians II.

To Timothy I.

To Timothy II.

To Titus

To Philemon

The Epistle to the Hebrews

The Epistle of James

The first and second Epistles of Peter

The first, second, and third Epistles of John

The Epistle of Jude

The Revelation of John

Of the Old Testament:

Genesis

Exodus

Leviticus

Numbers

Deuteronomy

Joshua

Judges

Ruth

I. Samuel

II. Samuel

I. Kings

II. Kings

I. Chronicles

II. Chronicles

Ezra

Nehemiah

Esther

Job

Psalms

Proverbs

Ecclesiastes

The Song of Songs

Isaiah

Jeremiah

Lamentations

Ezekiel

Daniel

Hosea

Joel

Amos

Obadiah

Jonah

Micah

Nahum

Habakkuk

Zephaniah

Haggai

Zechariah

Malachi

All which are given by inspiration of God, to be the rule of faith and life.(g)

(g) Luke 16:29, 31; Ephesians. 2:20; Revelation. 22:18, 19; 2 Timothy  3:16

3. The books commonly called Apocrypha, not being of divine inspiration, are no part of the canon of the Scripture; and therefore are of no authority in the Church of God, nor to be any otherwise approved, or made use of, than other human writings.(h)

(h) Luke 24:27, 44; Romans. 3:2; 2 Peter. 1:21.

Additionally, 2 Peter 1:21 tells us that men were carried, or moved by the Holy Spirit in the production of the prophecy of scripture. It is this fact alone – that God the Holy Spirit has personally moved each writer of scripture – that verifies the trustworthiness of the scriptures (Job 40:8, Psalm 119:160, Hebrews 6:18, Romans 3:4, 1 John 5:20). 

The scriptures are inerrant as well as infallible. Not only do they not err, meaning they possess no errors, but they are also incapable of erring; they are incapable of containing any errors. The Chicago Statement on Biblical Inerrancy declares that these terms have special value and they explicitly safeguard crucial positive truths of scripture. In Proverbs 30:5, we are told that every word of God is true, flawless, and tested, all giving the idea that the word of God has been proven true, is flawless, and has been put through the most rigorous of tests, and has come out on the other end of testing with no contradictions, no errors, and no missteps found. 

The inerrant nature of God's word is to be exemplified in the truthfulness of God, as he declares, “let God be found true and every man a liar” (Romans 3:4). The faithlessness and inconsistency of man cannot be grounds for determining that the same is true of God. The fact that man is so inconsistent and fickle in every moment of our lives, would immediately indicate that the word of God can be nothing other than divine in its origin. It does not logically follow that since man physically wrote the scripture that it is not trustworthy. It would be riddled with errors if that were the case. However,  nothing could be further from the truth, for, God calls himself the “God of truth” in Isaiah 65:16. 

Since the Bible is infallible, inerrant, and inspired, it must follow necessarily that it is also authoritative. The Bible records dozens of times when the prophets declare “thus says the Lord.” Also, in the New Testament, Jesus upholds all the words of the prophets and the law (Luke 24:44; Matthew 5:18), because he recognized them as the authoritative word of God, not only for those people at that time but for all people of all times. Furthermore, James tells us that whoever keeps the whole law but fails in one point has become accountable for all of it because all of God’s word is authoritative in our lives (Jas. 2:10). The entire Bible must be authoritative. Otherwise, it would become impossible to determine which aspects are and which are not authoritative, and in that case, the choice would be completely subject to the sinful desire of man to disobey God’s commands. This notion would and does lead to theological liberalism; taking from the scripture what we like while leaving and condemning what we do not. 

The inspiration, inerrancy, and authority of the Bible all relate to one another because they all necessarily require and flow into one another. Unless God inspired the Bible it cannot be inerrant or authoritative. Unless the Bible is inerrant and infallible and therefore without error, then it cannot be authoritative because there would always be doubt as to what – if anything – could be trusted as true.

Now, two questions remain: 1) how do you look at the scriptures, and 2) do you actually read the scriptures?