Charles H. Spurgeon on Psalms 15:3

After the positive comes the negative. "He that backbiteth not with his tongue." There is a sinful way of backbiting with the heart when we think too hardly of a neighbour, but it is the tongue which does the mischief. Some men's tongues bite more than their teeth. The tongue is not steel, but it cuts, and it's wounds are very hard to heal; its worst wounds are not with its edge to our face, but with its back when our head is turned. Under the law, a night hawk was an unclean bird, and its human image is abominable everywhere. All slanderers are the devil's bellows to blow up contention, but those are the worst which blow at the back of the fire. "Nor doeth evil to his neighbour." He who bridles his tongue will not give a licence to his hand. Loving our neighbour as ourselves will make us jealous of his good name, careful not to injure his estate, or by ill example to corrupt his character. "Nor taketh up a reproach against his neighbour." He is a fool if not a knave who picks up stolen goods and harbours them; in slander as well as robbery, the receiver is as bad as the thief. If there were not gratified hearers of ill reports, there would be an end of the trade of spreading them. Trapp says, that "the tale-bearer carrieth the devil in his tongue, and the tale-hearer carries the devil in his ear." The original may be translated, "endureth;" implying that it is a sin to endure or tolerate tale-bearers. "Show that man out!" we should say of a drunkard, yet it is very questionable if his unmanly behaviour will do us so much mischief as the tale-bearers insinuating story. "Call for a policeman!" we say if we see a thief at his business; ought we to feel no indignation when we hear a gossip at her work? Mad dog! Mad dog!! is a terrible hue and cry, but there are few curs whose bite is so dangerous as a busybody's tongue. Fire! fire!! is an alarming note, but the tale-bearer's tongue is set on fire of hell, and those who indulge it had better mend their manners, or they may find that there is fire in hell for unbridled tongues. Our Lord spake evil of no man, but breathed a prayer for his foes; we must be like him, or we shall never be with him.