Our Lord brings together, in our text, as is often His wont, two apparently contradictory ideas, in order, by the paradox, to fix our attention the more vividly upon His words. Fire destroys; salt preserves. They are opposites. But yet the opposites may be united in one mighty reality, a fire which preserves and does not destroy. The deepest truth is that the cleansing fire which the Christ will give us preserves us, because it destroys that which is destroying us. If you kill the germs of putrefaction in a bit of dead flesh, you preserve the flesh; and if you bring to bear upon a man the power which will kill the thing that is killing him, its destructive influence is the condition of its conserving one.
And so it is, in regard to that great spiritual influence which Jesus Christ is ready to give to every one of us. It slays that which is slaying us, for our sins destroy in us the true life of a man, and make us but parables of walking death. When the three Hebrews were cast into the fiery furnace in Babylon, the flames burned nothing but their bonds, and they walked at liberty in the fire. And so it will be with us. We shall be preserved by that which slays the sins that would otherwise slay us.
Let me lay on your hearts before I close the solemn alternative to which I have already referred, and which is suggested by the connection of my text with the preceding words. There is a fire that destroys and is not quenched. Christ's previous words are much too metaphorical for us to build dogmatic definitions upon. But Jesus Christ did not exaggerate. If here and now sin has so destructive an effect upon a man, O, who will venture to say that he knows the limits of its murderous power in that future life, when retribution shall begin with new energy and under new conditions? Brethren, whilst I dare not enlarge, I still less dare to suppress; and I ask you to remember that not I, or any man, but Jesus Christ Himself, has put before each of us this alternative--either the fire unquenchable, which destroys a man, or the merciful fire, which slays his sins and saves him alive.
Social reformers, philanthropists, you that have tried and failed to overcome your evil, and who feel the loathly thing so intertwisted with your being that to pluck it from your heart is to tear away the very heart's walls themselves, here is a hope for you. Closely as our evil is twisted in with the fibres of our character, there is a hand that can untwine the coils, and cast away the sin, and preserve the soul. And although we sometimes feel as if our sinfulness and our sin were so incorporated with ourselves that it made oneself, with a man's head and a serpent's tail, let us take the joyful assurance that if we trust ourselves to Christ, and open our hearts to His power, we can shake off the venomous beast into the fire and live a fuller life, because the fire has consumed that which would otherwise have consumed us.