For consider that the Gospel which proclaims Jesus as the Saviour is the only thing which deals with the deepest fact in our natures, the fact of sin; gives a personal Deliverer from its power; communicates a new life of which the very essence is righteousness, and which brings with it new motives, new impulses, and new powers.
Contrast with this the inadequate diagnosis of the disease and the consequent imperfection of the remedy which other physicians of the world's sickness present. Most of them only aim at repressing outward acts. None of them touch more than a part of the whole dreadful circumference of the dark orb of evil. Law restrains actions. Ethics proclaims principles which... it has no power to realize. It shows men a shining height, but leaves them lame and grovelling in the mire. Education casts out the demon of ignorance, and makes the demons whom it does not cast out more polite and perilous. It brings its own evils in its train. Every kind of crop has weeds which spring with it. The social and political changes, which are eagerly preached now, will do much; but one thing, which is the all-important thing, they will not do, they will not change the nature of the individuals who make up the community. And till that nature is changed any form of society will produce its own growth of evils. A Christless democracy will be as bad as, if not worse than, a Christless monarchy or aristocracy. If the bricks remain the same, it does not much matter into what shape you build them.
-From a sermon on Acts 19:11-17 in Expositions of Holy Scripture: Acts Chapter 13 to End by Alexander Maclaren (pp 176-7).