The unbridled tongue

Psalm 120: 2. Deliver my soul, O Lord, from lying lips, etc. 

An unbridled tongue is "vehiculum Diaboli", the chariot of the Devil, wherein he rides in triumph. Greenhorn doth describe the tongue prettily by contraries, or diversities: "It is a little piece of flesh, small in quantity, but mighty in quality; it is soft, but slippery; it goeth lightly, but falls heavily; it strikes soft, but wounds sore; it goeth out quickly, but burns vehemently; it pierces deep, and therefore not healed speedily; it hath liberty granted easily to go forth but it will find no means easily to return home; and being once inflamed with Satan's bellows, it is like the fire of hell." 

The course of an unruly tongue is to proceed from evil to worse, to begin with foolishness, and go on with bitterness, and to end in mischief and madness. See Eccl. 10:13. The Jew's conference with our Saviour began with arguments: "We be Abraham's seed," said they, etc.; but proceeded to blasphemies: "Say we not well that thou art a Samaritan, and hast a devil?" and ended in cruelty: "Then took they up stones to cast at him." John 8:33,48,59. This also is the base disposition of a bad tongue to hate those whom it afflicts: Pr 26:28. The mischief of the tongue may further appear by the mercy of being delivered from it, for,

1. So God hath promised it (John 5:15,21). "God saves the poor from the sword, from their mouth, and from the hand of the mighty," and "thou shalt be hid from the scourge of the tongue," or from being betongued, as some render it, that is, from being, as it were, caned or cudgelled with the tongues of others. "Thou shalt hide them in the secret of thy presence from the pride of man: thou shalt keep them secretly in a pavilion from the strife of tongues" (Ps 31:20); that is, from all calumnies, reproaches, evil speakings of all kinds. God will preserve the good names of his people from the blots and bespatterings of malicious men, as kings protect their favourites against slanders and clamours.

2. So the saints have prayed for it, as David: "Deliver my soul, O Lord, from lying lips, and from a deceitful tongue."—Edward Reyner.

Quoted in Charles Spurgeon's The Treasury of David, on Psalm 120. The original material is possibly from Reyner's 'Rules for the Government of the Tongue: together with Directions in six Particular Cases,' (1656)