Why ever disagree with anyone—much less battle him or her—over theology? Does it really matter so much whether or not people believe in God’s sovereignty as long as they’re saved? Do they really have to understand and uphold the orthodox doctrine of the Trinity? Is it all that important for them to believe in and understand inerrancy, progressive sanctification, and the host of other things Christians are unceasingly busy discussing and teaching and even fighting over?
Yes. Good theology is for our own good.
Paul several times in his letters uses phrases like “sound doctrine” or “sound words.” Interestingly, all of these appear in the Pastoral Epistles—the books concerned with telling pastors how to shepherd. He tells Timothy to “follow the pattern of the sound words” he heard from Paul (2 Tim. 1:13). He warns that there will be a time when people won’t endure “sound doctrine” (2 Tim. 4:3). An overseer is required to “be able to give instruction in sound doctrine and also to rebuke those who contradict it” (Titus 1:9; cf. 1 Tim. 1:10; 6:3; Titus 2:1, 8).
It is well known that the Greek word rendered “sound” (ὑγιαίνω) has another sense, “healthy.” I’m not saying it somehow really means “healthy” in these passages I’m discussing. I don’t think it does. It means “sound.” Whether or not Greek speakers in Paul’s day would have thought of “healthiness” when they heard the word, I don’t pretend to know. But the fact that English translations have almost universally gone with either “sound” or “wholesome” suggests to me that the word was a bit warmer than BDAG’s suggestion of “correct.” There’s a taste of “healthy” in both “sound” and “wholesome.” To be “sound of mind and body” is indeed to be healthy, and to eat things that are “wholesome” is to promote health.
One of my major purposes in teaching truth carefully is that it is what helps people the most. Believing, really believing, that God rules—really rules!—is wholesome when a mother has lost her unborn child in a miscarriage. It’s spiritually healthy to think right thoughts about God. God even said that it is by beholding Him in His Word that we are changed to be like Him (2 Cor. 3:18). Thinking and believing sound words about God promotes a soundness that gives us strength against spiritual diseases—worry, anger, envy, strife. I will fight, when necessary, to protect the pattern of sound words in Scripture not because I want my theological party to have political power in the church (God help me!) but because good theology is for my brother’s good.