"The fool's lips lead him into strife, and his mouth provokes a beating." - Proverbs 18:6

Proverbs
Chapter 18

1] In estrangement one seeks pretexts: with all persistence he picks a quarrel.
2] The fool takes no delight in understanding, but rather in displaying what he thinks.
3] With wickedness comes contempt, and with disgrace comes scorn.
4] The words from a man's mouth are deep waters, but the source of wisdom is a flowing brook.
5] It is not good to be partial to the guilty, and so to reject a rightful claim.
6] The fool's lips lead him into strife, and his mouth provokes a beating.
7] The fool's mouth is his ruin; his lips are a snare to his life.
8] The words of a talebearer are like dainty morsels that sink into one's inmost being.
9] The man who is slack in his work is own brother to the man who is destructive.
10] The name of the LORD is a strong tower; the just man runs to it and is safe.
11
The rich man's wealth is his strong city; he fancies it a high wall.
12] Before his downfall a man's heart is haughty, but humility goes before honors.
13] He who answers before he hears-- his is the folly and the shame.
14] A man's spirit sustains him in infirmity-- but a broken spirit who can bear?
15] The mind of the intelligent gains knowledge, and the ear of the wise seeks knowledge.
16] A man's gift clears the way for him, and gains him access to great men.
17] The man who pleads his case first seems to be in the right; then his opponent comes and puts him to the test.
18] The lot puts an end to disputes, and is decisive in a controversy between the mighty.
19] A brother is a better defense than a strong city, and a friend is like the bars of a castle.
20] From the fruit of his mouth a man has his fill; with the yield of his lips he sates himself.
21] Death and life are in the power of the tongue; those who make it a friend shall eat its fruit.
22] He who finds a wife finds happiness; it is a favor he receives from the LORD.
23] The poor man implores, but the rich man answers harshly.
24] Some friends bring ruin on us, but a true friend is more loyal than a brother.

Source: http://www.usccb.org/nab/bible/proverbs/proverb18.htm