Colossians 3:8
But now ye also put off all these; anger, wrath, malice, blasphemy,filthy communication out of your mouth.

Proverbs 15:1-4
A soft answer turneth away wrath: but grievous words stir up anger. The tongue of the wise useth knowledge aright: but the mouth of fools poureth out foolishness. The eyes of the LORD [are] in every place, beholding the evil and the good. A wholesome tongue [is] a tree of life: but perverseness therein [is] a breach in the spirit.