We have the New Testament largely because of the theological diseases that infected and afflicted the first-generation churches. The apostles wrote to clarify and remind early believers of things they had been taught, and to correct false doctrines that were springing up.

All of church history resembles the New Testament: remarkable outpourings of the Holy Spirit, gospel advances, churches planted, outbreaks of persecution and martyrdoms, doctrinal distortions and leadership abuses and all manner of sin causing churches to be, as the old hymn says, “by schisms rent asunder, by heresies distressed,” followed by Holy Spirit-empowered revival and reformation movements.

Best to Know Your Bible

To have knowledge of church history is good — really good. It helps us keep perspective. It helps us keep from being too euphoric and triumphalist in revival, too depressed and defeatist in tribulation, and too enamored of The Next Big Thing, the new method, strategy, or movement that promises to be The Answer. Church history helps us remember, “Is there a thing of which it is said, ‘See, this is new’? It has been already in the ages before us” (Ecclesiastes 1:10).

But it’s best to know our Bibles very well. The only proven antidote to the doctrinal and moral diseases that have always afflicted the churches of God is “holding fast to the word of life” (Philippians 2:16) and “not . . . go[ing] beyond what is written” (1 Corinthians 4:6). Church history serves to confirm this is true.

The Church-Preserving Power

Andrew Fuller (1754–1815) is a helpful example of one who honored the Bible’s voice above all others.

For most of Fuller’s adult life, he pastored a small Baptist church in the town of Kettering in central England. Most Christians today haven’t heard of Fuller. Those who have heard of him know him mainly for his role in founding the Baptist Missionary Society with William Carey, “the morning star of modern missions.” Fuller was one of Carey’s most faithful “rope holders” during Carey’s missionary and Bible-translation labors in India.

But God used Fuller not only as an early missions strategist and statesman, but also to stem the plague of false teaching that was killing Calvinistic Baptist churches in his day.

Disease Remedied by God’s Word

One deadly disease was so-called High-Calvinism (what we could call “hyper-Calvinism”), which distorted the doctrine of the sovereignty of God in election. It taught there is no need to use means (preaching, writing, urging, pleading) to convert unbelievers, since those means are only effective after regeneration. This disease made churches impotent and sterile. In one forty-year period, Fuller’s Baptist denomination shrunk from 220 to 150 churches.

Another disease was called Sandemanianism (after a Scottish theologian named Robert Sandeman), which distorted the doctrine of justification by faith alone. Sandeman, in trying to keep faith from becoming just another work to merit salvation, asserted that faith must only be the bare intellectual notion of who Jesus is and the significance of his work, given by God to a person’s mind apart from their will or affections. So true faith, according to Sandeman, could coexist with ungodliness in a person, since God “justifies the ungodly” (Romans 4:5).

It’s not hard to imagine the spiritual deterioration in churches when a “Christian” no longer needs to demonstrate any evidence, in behavior and heart, of saving faith.

Andrew Fuller believed and loved the Reformed doctrines of election and justification. But more than that, he knew his Bible well. He knew what God says about using means to reach unbelievers (Romans 10:14–15), and what God says about the evidence of saving faith (James 2:14–20). Because he knew the Bible so well, he could see where the High Calvinists and Sandemanians were going beyond what is written and thus building with cheap materials and destroying the temple of God’s people (1 Corinthians 3:12–17).

So Fuller gave himself relentlessly to treating sick churches, and inoculating healthy churches, with what the Bible actually teaches. His work, while unwavering, was not unwearying. Fuller frequently felt overwhelmed by the demands, adversity, and grief he endured.

While he pastored a church, contended for the faith, and helped advance the Great Commission, he saw eight of his eleven children and a wife die young. Nevertheless, through his faithful efforts, God used Fuller to help stem the plagues that afflicted many churches.

Read History — and Steep Yourself in Your Bible

Andrew Fuller is worth knowing. Read John Piper’s wonderful new short biography about Fuller (it’s only 56 pages), or if you prefer listening, John gave an excellent biographical message on Fuller’s life a few years back.

But Fuller would be the first to say that the best thing you can do for yourself, your family, your church, your neighbors, the persecuted church, and the cause of world missions is to be steeped in your Bible.

• The only way we can “walk in a manner worthy of the Lord, fully pleasing to him, bearing fruit in every good work and increasing in the knowledge of God” is to be “filled with the knowledge of [God’s] will in all spiritual wisdom and understanding” (Colossians 1:9–10).

• The only way we will be able to withstand satanic deception and sin’s temptation is letting “the word of Christ dwell in [us] richly (Colossians 3:16).

• The only way we will stand approved in “the day of Christ” will be if we “[hold] fast to the word of life” (Philippians 2:16).

We must submit to “the whole counsel of God” (Acts 20:27) and not allow the limits of our own understanding to place unbiblical limits on the “breadth and length and height and depth, and . . . the love of Christ that surpasses knowledge” (Ephesians 3:18–19). Plead with God for the strength to comprehend what is beyond our human ability to grasp (Ephesians 3:18).

And resolve not to go beyond what is written (1 Corinthians 4:6).