The canon of Scripture refers to all the books in the Christian Bible and Hebrew Scriptures that together constitute the complete and divinely inspired Word of God. Only the books of the canon are considered authoritative in matters of faith and practice. The idea of a closed canon is that the Bible is complete; no more books are being added to it. God is not appending His Word.
The canon of Scripture was determined by God, not men. Making this distinction is important. The accepted books were not considered inspired because humans determined that they should be part of the canon; they were included in the canon because God inspired them at the time they were written. God’s people were only responsible for discovering or recognizing the canon. The process of discovery started with Jewish scholars and rabbis and was finalized by the early Christian church by the end of the fourth century.
The development of a complete or closed canon of Scripture formed as the early church tested and discerned what was truly the divinely inspired Word of God. Humanly speaking, the process unfolded imperfectly, but ultimately God’s sovereign purpose prevailed.
Today Protestants include 66 books of the Old and New Testament in the canon. Roman Catholics and some Eastern Orthodox churches accept additional writings known as the Apocrypha, a set of books not considered authoritative or divinely inspired in Judaism and Protestant Christianity.
The most significant implication of a closed canon is that additional books cannot be added to the Bible and none of the books that are currently included can be removed. God has spoken.
A closed canon implies that other religious books that devotees purport to be inspired by God should be rejected as spurious. The Book of Mormon, the Quran, the Vedas, The Great Controversy, and Science and Health with Key to the Scriptures—all of these are works of men and women and not the product of God’s Holy Spirit.
A closed canon also implies that there are no apostles or prophets today who are receiving new messages from God. The church is gifted with teachers and preachers of the Word today, but anyone who claims a new revelation from God, proffers his or her message as divinely inspired, or assumes authority on par with the Bible is leading people astray. Sadly, many in the church give heed to dreams and visions shared from the pulpit and to those who falsely claim that “God spoke to me.”
But what if a truly prophetic book were discovered today? What if a lost letter written by the apostle Paul were found? Even if another epistle were found, and it could be verified as Pauline, we would not add it to the canon of Scripture. We assume that Paul wrote many letters to various groups over the course of his ministry, but most of them were not preserved, showing it was not God’s will for them to be included in the canon (see 2 Corinthians 7:8 for a possible reference to a non-canonical letter).
Jude, one of the last books to be included in the canon before it was closed, says, “Dear friends, although I was very eager to write to you about the salvation we share, I felt compelled to write and urge you to contend for the faith that was once for all entrusted to God’s holy people” (Jude 1:3). The words the faith in this passage refer to the sum of what Christians believe, all of the apostles’ teachings, or the whole body of Christian beliefs. In other words, everything we believe in the Christian faith has already been delivered or revealed to the saints through the apostles and prophets. Through the Scriptures, God has given us a final and complete body of knowledge for living the Christian faith.
An open canon would allow books or passages of Scripture to be added to the Bible through continued or ongoing revelation. By adding books to the canon, we would essentially be saying that the current Bible is incomplete, or lacking in some way.
Proverbs 30:5–6 cautions us not to add to God’s words: “Every word of God is flawless; he is a shield to those who take refuge in him. Do not add to his words, or he will rebuke you and prove you a liar.”
Deuteronomy 4:2 warns us not to add or to take away from God’s commands: “Do not add to what I command you and do not subtract from it, but keep the commands of the LORD your God that I give you” (see also Deuteronomy 12:32).
At the close of the book of Revelation, the last book of the Bible, we read a similar warning: “I testify to everyone who hears the words of the prophecy of this book: if anyone adds to them, God will add to him the plagues which are written in this book; and if anyone takes away from the words of the book of this prophecy, God will take away his part from the tree of life and from the holy city, which are written in this book” (Revelation 22:18–19)
Acknowledging a closed canon means accepting the idea that God has already revealed everything His children need to know. It also means that everything He has revealed in the Scriptures is divinely inspired. Nothing should be added, and nothing ought to be taken away or ignored.
A closed canon doesn’t mean God has ceased to reveal Himself to people today but that there will be no new revelation of truth outside of what He has already revealed in the Bible to the church. God has placed in the closed canon of Scripture everything we need to know about Himself, and about who we are, how we ought to live, and what will happen in the future (see 2 Peter 1:3).