As God works upon the heart by His Holy Spirit, man must cooperate with Him. The thoughts must be bound about, restricted, withdrawn from branching out and contemplating things that will only weaken and defile the soul. The thoughts must be pure, the meditations of the heart must be clean, if the words of the mouth are to be words acceptable to heaven, and helpful to your associates. . .
Volume 3, Bible Commentaries, page 1145