Mark records this instruction by Jesus as follows: “Go into all the world and preach the gospel to every creature. He who believes and is baptized will be saved; but he who does not believe will be condemned” (Mk. 16:15-16). Preaching is a form of teaching. So, Jesus instructed the apostles to “make disciples of all the nations” by teaching the gospel to them. Pertaining to those who would believe and be baptized, thus becoming disciples of Christ, the apostles were to continue “teaching them to observe all things” that Jesus had “commanded” them. Clearly, teaching is not just important, it is all important!
The apostle Paul stated that God’s plan is that we employ that same teaching method instructed by Jesus, namely preaching, “to save those who believe” (1 Cor. 1:21). Paul wrote to the Colossians, “Him we preach, warning every man and teaching every man in all wisdom, that we may present every man perfect in Christ Jesus” (Col. 1:28). What is God’s plan for bringing sinful mankind to salvation? Teaching!
Some would probably still try to distinguish between teaching the gospel and teaching doctrine. But, again, what does the word doctrine mean? Teaching. What did Jesus instruct to be taught in order to “make disciples of all the nations”? First the gospel and then “all things that I have commanded you;” (Matt. 28:19-20). In his first letter to Timothy, Paul equates “sound doctrine” with “the glorious gospel” (1 Tim. 1:10-11). From that text we can conclude that without doctrine there would be no gospel.
In his second letter to Timothy the apostle Paul warned of a time to come when people would “not endure sound doctrine.” They would find false teachers to scratch their “itching ears” with false doctrine, and they would “turn their ears away from the truth.” In order to guard against such Paul instructed Timothy to “Preach the word…with all longsuffering and teaching (KJV doctrine)” (2 Tim. 4:1-4).
One of the most pointed texts emphasizing the importance of getting doctrine right is found in John’s second letter: “Whoever transgresses and does not abide in the doctrine of Christ does not have God. He who abides in the doctrine of Christ has both the Father and the Son” (2 Jn. 9). As already noted in Jesus’ instruction to the apostles at his ascension, the doctrine of Christ includes the doctrines by Christ (Matt. 28:19-20).
Does doctrine matter? Only if you want to go to Heaven…