The tongue's power of blessing is simply incalculable. It can impart valuable knowledge, making others wiser. It can utter kindly sentences that will comfort sorrow or cheer despondency. It can breathe thoughts that will arouse, inspire, and quicken heedless souls, and even call up dead souls to life. It can sing songs which will live for ever in blessed influence and ministry. Such power we should consecrate to God and hold ever pure for him. The lips that speak God's name in prayer and Christian song, and that utter vows of fidelity to Christ, should never defile themselves with any form of corrupted speech. They should be kept only for Christ. No prayer should be oftener spoken by us than that of David in one of his psalms: "Set a watch, O Lord, before my mouth; keep the door of my lips" (Psalms 141:3). There is nothing in all our life to which most of us give less heed than to our words. We let them fly from our lips as the leaves fly from the trees when the autumn winds blow. Many people seem to think that words scarcely have a moral character. They watch their acts, their conduct, and then give full license to their tongues. This is not right. A true Christian should have a Christian tongue. Words have terrific power for harm if they are wrong words, and blessed, immortal power for good if they are holy words. We need to pray continually that God would keep the door of our lips and set a watch before our mouth. Only love should be permitted to interpret itself in speech. Bitterness and all evil should be restrained.
James 3:1-12: My brethren, be not many masters, knowing that we shall receive the greater condemnation. For in many things we offend all. If any man offend not in word, the same is a perfect man, and able also to bridle the whole body. Behold, we put bits in the horses' mouths, that they may obey us; and we turn about their whole body. Behold also the ships, which though they be so great, and are driven of fierce winds, yet are they turned about with a very small helm, whithersoever the governor listeth. Even so the tongue is a little member, and boasteth great things. Behold, how great a matter a little fire kindleth! And the tongue is a fire, a world of iniquity: so is the tongue among our members, that it defileth the whole body, and setteth on fire the course of nature; and it is set on fire of hell. For every kind of beasts, and of birds, and of serpents, and of things in the sea, is tamed, and hath been tamed of mankind: But the tongue can no man tame; it is an unruly evil, full of deadly poison. Therewith bless we God, even the Father; and therewith curse we men, which are made after the similitude of God. Out of the same mouth proceedeth blessing and cursing. My brethren, these things ought not so to be. Doth a fountain send forth at the same place sweet water and bitter? Can the fig tree, my brethren, bear olive berries? either a vine, figs? so can no fountain both yield salt water and fresh. (KJV)