When we say that the Bible is the canon, we mean two things:
1. First, we mean those specific books which compose the Bible.
2. Second, we mean that every book in the Bible has met the standard; it has measured up to the requirement of divine inspiration. The books of the Bible are called canonical because they have met the standard for being in the Bible.
But why is the canon significant?
The canon is significant because it is the rule of life for God's people. Our English word canon comes from the Greek word kanon, which means a straight rod, straight edge, or ruler. The word was used in biblical times to mean a standard or norm. The Apostle Paul uses the Greek word kanon in his letter to the church at Galatia: "Peace and mercy to all who follow this rule (kanon)" (Galatians 6:16).
It is vital that God's people know which books are canonical, so they can know with certainty which books to live by. Very early in the history of God's people, the first canonical books were recognized and preserved. Deuteronomy 31:24-26 tells us that the writings of Moses were kept with the ark of the covenant so their standard would not be forgotten:
After Moses finished writing in a book the words of this law from beginning to end, he gave this command to the Levites who carried the ark of the covenant of the Lord: "Take this Book of the Law and place it beside the ark of the covenant of the Lord your God. There it will remain as a witness against you."
We have a helpful illustration in the Old Testament itself about the significance of the canon. During a lengthy time of wide-spread disobedience in Israel's history, the Scriptures were disregarded and stored away in a dark corner of the temple. Finally, the servants of king Josiah, a new king devoted to God, found the lost books. When they made this discovery and read the books, the people were filled with both joy and fear. Joy for again having the word of God to read and follow, but also fear as they read God's will for their lives and realized how far they were from following it. You can read about their love and respect for God's word as their rule of life in 2 Kings 22:8-23:3.
The books which formed the canon of the Old Testament were routinely used in the Temple and later in the synagogue for worship services and instruction. Jesus read and taught from these same books whenever he gave instruction in the synagogues (see Luke 4:15-21), and they were his rule of life in all that he did (see Luke 4:4, 8, 12). The early Christian church also recognized the Old Testament canon as "God breathed" and "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 3:16-17).
