Doctrine is the revealed truth of God defined and taught by the church in conversation with the Bible and the whole Christian tradition. Doctrine is for the growth of believers as well as for the whole world. The Latin word doctrina literally means teaching. Indeed, our English Bible most commonly translates the Greek word for doctrine with our word teaching. If a person teaches then they are communicating doctrine. It may be bad doctrine or good doctrine but it is doctrine. This is why I am always puzzled by people who say, "Just teach the Bible. Do not teach us doctrine."
The church, at least on the pages of the New Testament, appears as a community of learners. Some of these learners became teachers of the early church. All Christians were to be engaged in the lifelong task of taking in, meditating upon, and living out Christian doctrine. The most important of all Christian doctrines is the gospel of Jesus Christ, the good news. This doctrine most feeds our minds and hearts so that we can know and love Jesus.
A disciple is a life-long learner of doctrine. The Greek word for disciple is actually learner. The church in the New Testament is seen as a fellowship of learners who gather to worship the living Christ and then learn from him through teachers and each another. Each Christian is called to learn more about Christ and then to obey what they learn.
There is a real danger that a congregation can become doctrinally dull. The writer to the Hebrews rebukes some early Christians when he says, “You have become dull of hearing. For though by this time you ought to be teachers, you need someone to teach you again the basic principles of the oracles of God. You need milk, not solid food . . . solid food is for the mature” (Hebrews 5:11–14).
Doctrine is taught in many ways. Sermons, classes with instruction, devotional talks, catechisms, printed books and audio-visual resources can all help to teach doctrine to the church. Perhaps the best way to teach sound doctrine, beside careful preaching and teaching, is through worship itself. This is especially truth when the worship is structured around the great themes of the Christian faith. This will usually result in carefully planned liturgies. (All worship has elements of liturgy in it, some of it carefully designed and theologically congruent.) By all of these means Christians can hear the faith and assimilate it into their hearts.
Faithfulness to sound doctrine promotes spiritual health. Doctrine is not just a collection of my ideas and your ideas. Rightly understood and taught doctrine is a declaration of what the Lord has said for our collective benefit. If doctrine is God’s gift to the church then we need the Holy Spirit to make it live in our midst. No doctrinal instruction should be undertaken as simply an exercise in learning a few unrelated, or mysterious, truths. God gives gifts to men and women so they can teach the church. The church should give thanks for these gifts and listen to them prayerfully.