Matthew 12:35

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

Ephesians 4:29

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

Colossians 4:6

Let your speech be always with grace, seasoned with salt, that ye may know how ye ought to answer every one.

Treasury of Scripture Knowledge

Summary

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

Bible References

General references

Matthew 12:35
A good man out of the good treasure bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.
Ephesians 4:29
Let no corrupt discourse proceed out of your mouth, but that which is good, to the use of edifying, that it may minister grace to the hearers.
Colossians 4:6
Let your speech be always with grace, seasoned with salt, that ye may know how ye ought to answer every one.