Doctrine and doing are like the two chemical ingredients of salt, which is composed of two poisons: sodium and chlorine. If we ingested either of the two poisons, we would die. But if we combine them properly, we have sodium chloride, which is the common table salt that gives flavor to our food and indeed life and health to our bodies. So, too, are faith and works inseparable.
Baker Books , 1500 Illustrations for Biblical Preaching, by Michael P. Green