Throughout the New Testament the inspired writers use the word doctrine some 49 times. That certainly is a significant number in light of those who claim that doctrine is not important.
Doctrine comes from the Greek word which means “teaching,” or more appropriately, one’s “system” or “arrangement of teaching.” In other words, it refers to what one teaches collectively. For example, when Jesus came to the conclusion of the Sermon on the Mount, the Bible says, “the people were astonished at His doctrine” (Matt. 7:28). This did not refer to one thing that he taught, but rather all that He taught on that occasion. So the term encompasses all that one teaches.
It is said of the early church, “And they continued stedfastly in the apostle’s doctrine...” (Acts 2:42). The church was careful to follow the collective teachings of the apostles, and rightly so, for they were guided “into all truth” (John 16:13). And that divinely guided doctrine has been given to us in the New Testament. Since we have the inspired doctrine of Christ, then we must be careful to follow and observe all that it teaches. (Note: The doctrine of Christ and the apostle’s doctrine are one and the same.)
Paul told Timothy, “Take heed unto thyself, and unto the doctrine; continue in them: for in doing this thou shalt both save thyself, and them that hear thee” (1 Tim. 4:16). If there was any question as to the importance of doctrine, Paul has just made it plain that the doctrine of Christ is essential to one’s salvation!
Is doctrine important? Let the apostle John answer the question for us. “Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son. If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed: For he that biddeth him God speed is partaker of his evil deeds” (2 John 9-11).