18 But those things which proceed out of the mouth come forth from the heart; and they defile the man.

19 For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies:

20 These are the things which defile a man: but to eat with unwashen hands defileth not a man.

Psalm 39:1

39 I said, I will take heed to my ways, that I sin not with my tongue: I will keep my mouth with a bridle, while the wicked is before me.

James 3:

1My brethren, be not many masters, knowing that we shall receive the greater condemnation.

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.

3 Behold, we put bits in the horses' mouths, that they may obey us; and we turn about their whole body.

4 Behold also the ships, which though they be so great, and are driven of fierce winds, yet are they turned about with a very small helm, whithersoever the governor listeth.

5 Even so the tongue is a little member, and boasteth great things. Behold, how great a matter a little fire kindleth!

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.

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:

8 But the tongue can no man tame; it is an unruly evil, full of deadly poison.

9 Therewith bless we God, even the Father; and therewith curse we men, which are made after the similitude of God.

10 Out of the same mouth proceedeth blessing and cursing. My brethren, these things ought not so to be.

11 Doth a fountain send forth at the same place sweet water and bitter?

12 Can the fig tree, my brethren, bear olive berries? either a vine, figs? so can no fountain both yield salt water and fresh.

13 Who is a wise man and endued with knowledge among you? let him shew out of a good conversation his works with meekness of wisdom.

1 Cor 15:33

33 Be not deceived: evil communications corrupt good manners.

 Eph 4:29

29 Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace unto the hearers.

Math 12:33-37

33 Either make the tree good, and his fruit good; or else make the tree corrupt, and his fruit corrupt: for the tree is known by his fruit.

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

35 A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.

36 But I say unto you, That every idle word that men shall speak, they shall give account thereof in the day of judgment.

37 For by thy words thou shalt be justified, and by thy words thou shalt be condemned.

 James 3:13

13 Who is a wise man and endued with knowledge among you? let him shew out of a good conversation his works with meekness of wisdom.

 1 Pet 2:12

12 Having your conversation honest among the Gentiles: that, whereas they speak against you as evildoers, they may by your good works, which they shall behold, glorify God in the day of visitation.

 1 Pet 3:16

16 Having a good conscience; that, whereas they speak evil of you, as of evildoers, they may be ashamed that falsely accuse your good conversation in Christ.

 1 Pet 4:11

11 If any man speak, let him speak as the oracles of God; if any man minister, let him do it as of the ability which God giveth: that God in all things may be glorified through Jesus Christ, to whom be praise and dominion for ever and ever. Amen.

Titus 2:7-8

7 In all things shewing thyself a pattern of good works: in doctrine shewing uncorruptness, gravity, sincerity,

8 Sound speech, that cannot be condemned; that he that is of the contrary part may be ashamed, having no evil thing to say of you.

 2 Sam 23:2

2 The Spirit of the Lord spake by me, and his word was in my tongue.

 Job 6:30

30 Is there iniquity in my tongue? cannot my taste discern perverse things?

 Job 15:5

5 For thy mouth uttereth thine iniquity, and thou choosest the tongue of the crafty

 Psalm 37:30

30 The mouth of the righteous speaketh wisdom, and his tongue talketh of judgment.

 Psalm 50:23

23 Whoso offereth praise glorifieth me: and to him that ordereth his conversation aright will I shew the salvation of God.

 Eph 2:3

3 Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others.

 Eph 4:22

22 That ye put off concerning the former conversation the old man, which is corrupt according to the deceitful lusts;

 Phil 1:27

27 Only let your conversation be as it becometh the gospel of Christ: that whether I come and see you, or else be absent, I may hear of your affairs, that ye stand fast in one spirit, with one mind striving together for the faith of the gospel;

 1 Tim 4:12

12 Let no man despise thy youth; but be thou an example of the believers, in word, in conversation, in charity, in spirit, in faith, in purity.

 1 Pet 1:15

15 But as he which hath called you is holy, so be ye holy in all manner of conversation;

 2 Pet 2:7

7 And delivered just Lot, vexed with the filthy conversation of the wicked:

 2 Pet 3:11

11 Seeing then that all these things shall be dissolved, what manner of persons ought ye to be in all holy conversation and godliness,

 Prov 18:21

21 Death and life are in the power of the tongue: and they that love it shall eat the fruit thereof.

 1 Cor 15:33

33 Be not deceived: evil communications corrupt good manners.