Carl Trueman gave a lecture for the Evangelical Library West on the US theologian J. Gresham Machen and his disputes with theological liberalism. Many of Machen's concerns are relevant today . . .
The first thing Machen seeks to demonstrate in his work is the importance of doctrine, that is, of the church's verbal declaration of what it actually believes to be true. Indeed, while this topic occupies the first chapter, it is without doubt the underlying theme and presupposition of the entire work without which the rest really makes no sense at all.
To establish the importance of doctrine as such, Machen makes a number of points.