Miller makes a classic error in pitting "practitioners" against teachers and scholars. His argument runs something like this: Practitioners are good because they do. Teachers are trouble because they argue over details that don't matter too much.
Simplistic? Immensely so. Historically reliable? Not at all. What about Jesus who declared the imperative of belief in the truth? What about Paul? Other than Jesus has there ever been a man who more beautifully wed scholarship and practice? Augustine? Athanasius? What can we say about Luther, Calvin, or Knox? These were men committed to the right proclamation and practice of the truth. Miller's sloppy approach to the topic is inexplicable.
Owen Strachen has a thoughtful response to Miller HERE.
I do wonder if Miller, himself something of a bardsman-theologian, bites off a bit more than he can chew in his essay. His heart for Christian unity is commendable, but his understanding of ecclesial division seems characteristically youthful. Scripture is the Word of God; it demands careful handling (2 Tim. 2:15). From the birth of the church, Christians have given their time, their energy, even their very lives to nourish the church and keep it from error. We see this in countless historical examples: Athanasius suffering at the hands of his detractors to champion the then-fragile doctrine of the Trinity, Martin Luther risking his very life to promote the final authority of Scripture, Charles Spurgeon heroically fighting the down-grade in post-Victorian England. Courageous defense, nuanced discernment, necessary separation from false teachers—these traits don’t necessarily play well in postmodernia. They do, however, sustain and strengthen the church by God’s grace (see Rom. 12; 2 Tim. 1; 2 Pet. 2).