Overcoming Sin and Temptation (Foreword by John Piper)

The ground of this efficacy of sin by deceit is taken from the faculty of the soul affected with it. Deceit properly affects the mind; it is the mind that is deceived. When sin attempts any other way of entrance into the soul, as by the affections, the mind, retaining its right and sovereignty, is able to give check and control unto it. But where the mind is tainted, the prevalency must be great; for the mind or understanding is the leading faculty of the soul, and what that fixes on, the will and affections rush after, being capable of no consideration but what that presents unto them. Hence it is, that though the entanglement of the affections unto sin be oftentimes most troublesome, yet the deceit of the mind is always most dangerous, and that because of the place that it possesses in the soul as unto all its operations. Its office is to guide, direct, choose, and lead; and “if the light that is in us be darkness, how great is that darkness!” [Matt. 6:23].

As all the fuel in the world, all the fabric of the creation that is combustible, being cast into the fire, will not at all satisfy it, but increase it, so is it with satisfaction given to sin by sinning—it does but inflame and increase. If a man will part with some of his goods unto an enemy, it may satisfy him; but enmity will have all, and is not one whit the more satisfied than if he had received nothing at all—like the lean cattle that were never the less hungry for having devoured the fat. You cannot bargain with the fire to take but so much of your houses; you have no way but to quench it. It is in this case as it is in the contest between a wise man and a fool: “Whether he rage or laugh, there is no rest” (Prov. 29:9). Whatever frame or temper26 he be in, his importunate27 folly makes him troublesome. It is so with this indwelling sin: whether it violently tumultuate,28 as it will do on provocations and temptations, it will be outrageous in the soul; or whether it seem to be pleased and contented, to be satisfied, all is one, there is no peace, no rest to be had with it or by it. Had it, then, been of any other nature, some other way might have been fixed on; but seeing it consists in enmity, all the relief the soul has must lie in its ruin.

The more men exercise their grace in duties of obedience, the more it is strengthened and increased; and the more men exert and put forth the fruits of their lust, the more is that enraged and increased in them—it feeds upon itself, swallows up its own poison, and grows thereby.