This sponsored post is adapted from the all-new ESV Systematic Theology Study Bible, which features 400+ doctrinal summaries explaining core doctrines of the Christian faith and connecting them to specific Scripture passages—all designed to help you see how sound theology arises from the pages of the Bible.
What Is Doctrine?
No one can say “Jesus is Lord” (1 Cor. 12:3; Rom. 10:9) without speaking in a deeply doctrinal way, because this simple statement rests on profound biblical truths. It assumes that Christ is the eternal second member of the Trinity, who became uniquely God incarnate, was set forth as our substitutionary atonement, was raised from the dead having conquered all evil, and is now reigning sovereignly over all reality (Eph. 1:20–22).
But what is doctrine? Put simply, it is the way the central themes of God’s revelation in Scripture are summarized and taught. This teaching builds on their development through the Old Testament. It sees them as having culminated in Christ’s incarnation, words, and work. His teaching (Matt. 7:28; Mark. 1:22; John 7:16) was then expanded and applied by the apostles. Paul placed his own teaching side-by-side with the “preaching of Jesus Christ” (Rom. 16:25; cf. 1 Thess. 4:2). All of this was committed to writing under the inspiration of the Holy Spirit. These inspired writings are now preserved within the biblical canon. This revealed Word defines for us how we should think about God, ourselves, our world, the church, and the future.
Christian doctrine is present in different ways in the New Testament. Most often, of course, we meet it in the doctrinal sections in the epistles (e.g., Romans 1–8; Ephesians 1–3). But it is there in other ways too, pointing to the fact that doctrine had become part of the daily life of the early churches. Some early hymns are now embedded in the New Testament text (e.g., Phil. 2:5–11; probably 1 Tim. 3:16), and in them we see strong doctrinal elements. At other times, the apostolic teaching is crystallized into small creedal statements (e.g., Paul’s set of “trustworthy” sayings in 1 Tim. 1:15; 3:1; 4:8–9; 2 Tim. 2:11–13; Titus 3:4–8). Other passages seem to have a creedal form (e.g., Rom. 1:3–4; 10:8–9; Col. 1:13–20).
This doctrine underlies and, indeed, explains the practice of Christian faith. There is, in fact, no Christian ethic without a foundation of Christian doctrine. The daily practice of this faith is the daily living out of its doctrine. Apostolic Christianity was doctrinal in both shape and substance. It was about the doctrines of God, creation, human nature, Christ, redemption, the church, and the consummation of Christ’s kingdom. Apart from these doctrines, there is no Christian faith.
Why Is Doctrine Important?
Although apostolic doctrine was central to the life of the earliest churches, this centrality has not always been easy to preserve. Indeed, many of the great reforming moments that came later were really moments of recovery. Lost ways of doctrinal thinking and lost biblical doctrines were retrieved and made central once again. The reason for the church’s rather checkered history in this regard is quite simple: the content of this doctrine, as well as its function in the life of the church, is at the heart of the church’s spiritual warfare.
In the churches of John’s day, both “the Spirit of truth and the spirit of error” (1 John 4:6) were present. They are today, too. The Spirit of truth was heard in the apostolic teaching. Now it is heard through Scripture and through those who teach and expound that Scripture accurately. The spirit of error lives on in false teachers. The Spirit of truth and the spirit of error each have their respective audiences.
Satan’s strategy is to oppose, subvert, and mute the content of biblical doctrine and dislodge it from its place in the church’s life. God, though, has placed in the Christian’s hand a weapon for defense. It is the very truth under attack. It is what Paul calls the “belt of truth” and “sword of the Spirit” (Eph. 6:14, 17)—the Bible. These are parts of the Christian’s armor.
This explains a series of admonitions given in the New Testament that aim to protect the Bible’s doctrinal truth and secure its function in Christian life. Christians, in other words, stay within the Bible’s doctrinal parameters. They are to persist in this doctrine, follow it, guard it, stand firm in it, and hand it on intact. They do not venture outside of it, for that is where faith becomes shipwrecked (1 Tim. 1:19–20). They resist its alternatives. They know this truth is entirely sufficient for life despite uncertainties and suffering. Later, of course, this truth was formulated into the Protestant principle of sola Scriptura.
It is the Bible’s truth that sustains, strengthens, and guides us. This is why Paul speaks of it as he does. It is, he says, made up of “sound words” (2 Tim. 1:13). It is “sound teaching” (2 Tim. 4:3) and “sound doctrine” (Titus 2:1; 1:9). It is in accord with the “sound words of our Lord Jesus Christ” (1 Tim. 6:3). This word, translated here as sound, is used also of physical health.
These references to “sound” teaching and doctrine, then, are a reminder to us that from such teaching the church’s strength arises. From it comes its health. It is what reverses spiritual ills and, sometimes, even deep paralysis. It is what makes churches whole. It is what lays the foundation for their vitality as well as their longevity.
This is why biblical doctrine is important. This is why it is essential.