James 3:2 NIV

1 Peter 3:10 niv
For, “Whoever would love life and see good days must keep their tongue from evil and their lips from deceitful speech.

James 1:26 niv
Those who consider themselves religious and yet do not keep a tight rein on their tongues deceive themselves, and their religion is worthless.

James 3:5-6 niv
Likewise, the tongue is a small part of the body, but it makes great boasts. Consider what a great forest is set on fire by a small spark. The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell.

Matthew 12:37 niv
For by your words you will be acquitted, and by your words you will be condemned.”

Proverbs 13:3 niv
Those who guard their lips preserve their lives, but those who speak rashly will come to ruin.