Ephesians 4:29
Let no corrupt communication go forth out of your mouth, but if anything is good unto edification of need, in order that he may give grace to those who hear.
Matthew 12:35-37
The good man, out of the good treasure (heart) brings forth good things: and the wicked man out of the wicked treasure (heart) brings forth wicked things.
Colossians 4:6
Let your word be always with grace, seasoned with salt, that you may know how it behooves you to answer each one.
Titus 1:10-11
For many are incorrigible, speaking vain things and egotistical, especially those from the circumcision,
James 3:6-9
The tongue, a fire, the world of iniquity: the tongue sits down in the midst of our members, and corrupting the whole body, and setting on fire the course of nature; and it is set on fire from hell.
Romans 10:14-15
Then how can they call on him on whom they have not believed? and how can they believe on him of whom they have not heard? and how shall they hear without a preacher?
2 Corinthians 2:16
unto the latter a savour from death unto death; but unto the former a savour from life unto life. And who is sufficient for these things?
2 Corinthians 11:15
Then it is no great wonder if his ministers are transformed as the ministers of righteousness; whose, end shall be according to their works.
2 Peter 2:18
For speaking swelling words of vanity, in the lusts of the flesh they beguile with their impurities, those that have but partially escaped, who are still moving about in their delusion;