Ephesians 4:29
Let no impure speech come out of your mouth, but whatever is good for needful edification, that it may give grace to the hearers:
Matthew 12:35-37
The good man, out of his good treasury, brings forth good things; and the evil man, out of his evil treasury, brings forth evil things.
Colossians 4:6
Let your speech be always with grace, seasoned with salt, that you may know how you ought to answer every one.
Titus 1:10-11
For there are many unruly and vain talkers and deceivers, especially those of the circumcision,
James 3:6-9
And the tongue is a fire, the world of iniquity. So is the tongue placed among our members, defiling the whole body, setting on fire the course of life, and being set on fire by hell.
Romans 10:14-15
How, then, shall they call on him in whom they have not believed? And how shall they believe in him of whom they have not heard? And how shall they hear without a preacher?
2 Corinthians 2:16
to the one, we are the odor of death ending in death; to the other, the odor of life ending in life: and who is sufficient for these things?
2 Corinthians 11:15
Therefore, it is no great thing if his ministers also transform themselves so as to be like the ministers of righteousness; of such, the end shall be according to their works.
2 Peter 2:18
For by speaking boastful words of folly, they allure through the lusts of the flesh, and through lasciviousness, those who had really escaped from those who live in error.