But here St. Peter has prescribed an appropriate remedy,--namely, obedience to truth in the Spirit, as Scripture also has done in other places,--as Isaiah xi.: "Faith shall be the girdle of his reins." This is the true plaster that girds the reins, for it must proceed from within outward, not from without inward. For it has penetrated into the flesh and blood, the marrow and other parts of the living system; it is not outward in the dress or clothing. Therefore it is not to be expected that we should subdue lust with outward things; we may weaken the body and destroy it with fastings and labors, but the evil lusts are not thereby banished; yet faith can subdue them, and guard them, that they shall be compelled to give the Spirit place. So likewise speaks the prophet Zachariah, ix., of the wine which Christ has, whereby the pure grow, and of which he gives them to drink. Other wine usually invites to wicked lust, but this wine,--that is, the Gospel,--subdues it, and makes the heart chaste. This is what St. Peter speaks of when any one heartily embraces the truth, and is obedient to it in spirit. This is the true help and the most powerful remedy for it, since you will find none which can still all evil thoughts like it; for if this enters our hearts, evil inclinations quickly leave; let whoever will try it, he shall find it true, and whoever has tried it, knows it well; but the devil lets no one easily attain it, and comprehend the word of God so as to delight in it; for he well knows how powerful it is to subdue evil lusts and thoughts. St. Peter, therefore, would here say, if you would remain chaste, then must you render obedience to the truth in the Spirit, that is,--we must not only read and hear the word of God, but apprehend it in our hearts. Therefore it is not enough that a man should preach or hear the Gospel once, but he must ever press after it and persevere; for such grace does the word possess, that the more we taste it the more delightful it is; although there is, throughout, one and the same doctrine of faith, yet it cannot be listened to too much where the heart is not wanton and untamed. _To unfeigned love of the brethren._ To what end, then, are we to live a chastely holy life? In order that we may be saved thereby? No! but in order that we may be useful to our neighbor. What am I to do that I may restrain my sin? I am to have obedience to the truth in the Spirit. But why am I to restrain it? In order that I may be of service to others, for I must first control my body and the flesh by the Spirit, and thus I can afterward be of service to others.--It follows further: