There are over 150 verses in Proverbs on words and the use of our tongues. In other words, almost one of every six verses is on how we speak! I will summarize the main points by addressing five questions.
1. What value or importance do our words have?
See 10:20; 20:15 (cf. Mt. 13:45-46).
2. What do they tell us about a person?
Words are a barometer, an index, a revelation of what is in the heart. See esp. Matt. 12:34-37; Prov. 10:6,20,32; 12:6,13; 15:2,28; 17:7. A person's speech is a reflection of his/her character. Nothing is more a test of our maturity than our speech.
3. What can they accomplish?
a. they are capable of destroying the one who speaks
See 17:20; 18:6-7. Although the fool does not deliberately pursue his own destruction, his rash, impetuous, inflammatory speech invites punishment and rebuke. He alienates himself from others and incurs the denunciation of all.
See 14:3. Again, careless speech inevitably leads to one's own destruction. Just as the fool's words guarantee his punishment, the wise man's words secure and protect him. "Many have felt the lash upon their backs for the want of a bridle on their tongues" (Matthew Henry).
b. they can be either a source of peace or a cloak for violence
See 10:11. Just as a deep well supplies the thirsty man with refreshing waters, so also do the words of the righteous refresh and console and preserve all around him. It is the opposite with the wicked.
c. in words lies the power of persuasion
d. in words lies the power of perversion
See 16:27-28. The word translated "worthless" is better rendered "perverse". This man is deranged and therefore destructive. He is the sort who has no desire to use language constructively to make friends; he is obsessed with using it destructively to separate them. He excavates the soil of interpersonal relationships until he has unearthed scandal. His speech causes searing pain like a scorching fire.
4. What kind of words/speech does Proverbs condemn?
a. dishonest, lying speech
See 4:24 (cf. Ps. 12:1-4); 12:19,22; 20:17. Truth endures whereas lies are fragile and ephemeral. Cf. Rev. 22:14-15.
See 12:17; 14:5,25; 19:5,9,28.
See 10:18; 11:13; 20:19 (one who breaks a confidence). See also 18:8, where the word translated "dainty morsels" comes from a root meaning "to swallow greedily". Slander is eagerly gulped down by a person disposed to listen to it, just as a glutton helps himself freely to tempting food. Also, in 26:20-21 we see that slander and gossip are the fuel that stokes the fire of dissension.
See 28:23; 29:5. His words of praise and flattery are a way of disarming you, of putting you at ease, of making you feel secure and comfortable in his presence; such flattery is really a snare for your feet for his purpose is sinister.
5. What kind of words/speech does Proverbs commend?
a. speech that is calm, gentle, pleasant
See 25:15 (15:1,4). Gentle speech, rather than harsh words, will more effectively overcome stubborn opposition.
On pleasant speech, see 15:26 and 16:24. Honey is both pleasant to the taste and of medicinal value; so also with gracious, pleasant words.
b. words that are appropriate to the occasion and few in number
See 10:14,19; 12:16,18. This latter verse (particularly v. 16) is quite instructive. The fool's rejoinder to an insult or accusation is always the immediate knee-jerk; it is emotional and ill-considered; it is a blind retaliatory swipe with little if any reason in it. McKane explains:
"He reacts like an injured animal and so his opponent knows that he has been wounded. The sagacious or shrewd man, on the contrary, has mastered any tendency towards impetuosity and has learned to hide his feelings. Even when he is insulted he maintains a front of imperturbability and does not give his adversary the satisfaction of observing the effect of his wounding words. He knows that it is better to sleep on an insult than to react emotionally and advertise how much one is hurt" (442).
Notice how Jesus responded to his accusers in Matt. 26:62-68; 1 Pt. 2:23.
Proverbs 15:23,28 and 25:11 stress the importance of choosing the proper time or occasion for our words. When we speak is often more important than what we say. Even the most priceless truths can fall uselessly to the ground if uttered at the wrong time.
"If your lips would keep from slips,
Five things observe with care;
To whom you speak; of whom you speak;
and how, and when, and where."
This principle is confirmed in 17:27-28 (cf. 18:2). Economy of words, careful timing, and judiciously chosen statements are the mark of the wise person. Even a fool can hide his mental and moral deficiencies from others just by keeping his mouth shut.
Finally, consider what appears to be a contradiction in 26:4-5. However, it is not our author's point to deny the validity of v. 4 by asserting v. 5. Wisdom sayings are always wedded to a particular situation. Verse 4 is the right advice for one kind of situation and v. 5 for another. The second half of each verse indicates that different circumstances are in view. According to v. 4b, there are times when one should let the fool ramble on and offer no rejoinder. If allowed to continue his babbling he will inevitably discredit himself. If you insist on responding it may well appear that you are of like mind with him. According to v. 5b, we see that in other circumstances it may be unloving to keep silent. In this latter situation, "it may be more important that he should be disabused of his illusions than that you should pursue a course which has the least risk for yourself" (McKane, 596). Often it is to the fool's own advantage that he be shown the folly of his words. As Bridges explains:
"Silence may sometimes be mistaken for defeat. Unanswered words may be deemed unanswerable, and the fool become arrogant, more and more wise in his own conceit. An answer therefore may be called for; yet not in folly, but to folly; not in his foolish manner, but in the manner which his foolishness required; not according to his folly, but according to thine own wisdom" (486-87).
c. words which, though painful, are loving
In 27:5-6 our author has in mind "speaking the truth in love." Even when our words injure, for a time, the self-esteem of a friend, or perhaps hurt his/her feelings, such words are a higher expression of love and affection than keeping silent and feigning approval.