J. Gresham Machen:
Indeed nothing makes a man more unpopular in the controversies of the present day than an insistence upon definitions of terms. Men discourse eloquently today upon such subjects as God, religion, Christianity, atonement, redemption, and faith, but they are greatly incensed when they are asked to tell in simple language what they mean by these terms. You speak of Christ? What Christ? You speak of atonement? What atonement? What is the nature of the atonement? Faith? What kind of faith? What is the nature of the faith you speak of?
It can feel tedious at times, and perhaps some of our rigorous “definers” lack charity, but where would the church be without careful attention to precise language? How weak and impoverished would the faith be if we never bothered to define the Trinity, or justification, or inerrancy? And how much healthier will we leave the church if we carefully define terms like missional, social justice, and gospel? Liberalism grows where meanings are assumed and careful definitions are eschewed.