Proverbs 10:19

10:19 In the multitude of words there wanteth not sin: but he that refraineth his lips [is] wise.

Proverbs 13:16

13:16 Every prudent [man] dealeth with knowledge: but a fool layeth open [his] folly.

Proverbs 29:11

29:11 A fool uttereth all his mind: but a wise [man] keepeth it in till afterwards.

Proverbs 29:20

29:20 Seest thou a man [that is] hasty in his words? [there is] more hope of a fool than of him.

Ecclesiastes 10:12-14

10:12 The words of a wise man’s mouth [are] gracious; but the lips of a fool will swallow up himself. 10:13 The beginning of the words of his mouth [is] foolishness: and the end of his talk [is] mischievous madness. 10:14 A fool also is full of words: a man cannot tell what shall be; and what shall be after him, who can tell him?

Matthew 12:34

12:34 O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh.

Titus 1:10-11

1:10 For there are many unruly and vain talkers and deceivers, specially they of the circumcision: 1:11 Whose mouths must be stopped, who subvert whole houses, teaching things which they ought not, for filthy lucre’s sake.

James 3:6-8

3:6 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. 3:7 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: 3:8 But the tongue can no man tame; [it is] an unruly evil, full of deadly poison.

James 3:2

3:2 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.

Ecclesiastes 2:18

2:18 Yea, I hated all my labour which I had taken under the sun: because I should leave it unto the man that shall be after me.