Matthew 12:35

The good person produces good things from his storehouse of goodness. But the evil person produces bad things from his storehouse of evil.

Ephesians 4:29

Do not allow unwholesome [Note: The Greek word for "unwholesome" is "rotten, diseased"] language to come from your mouth, but only what is helpful for building up those who need it, so that you can impart favor [i.e., benefit] to those who listen [to you].

Colossians 4:6

Your speech should always be favorable, seasoned with salt [i.e., interesting and appropriate], so that you may know how to properly answer each person [you talk with].

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
The good person produces good things from his storehouse of goodness. But the evil person produces bad things from his storehouse of evil.
Ephesians 4:29
Do not allow unwholesome [Note: The Greek word for "unwholesome" is "rotten, diseased"] language to come from your mouth, but only what is helpful for building up those who need it, so that you can impart favor [i.e., benefit] to those who listen [to you].
Colossians 4:6
Your speech should always be favorable, seasoned with salt [i.e., interesting and appropriate], so that you may know how to properly answer each person [you talk with].