Proverbs 15:1 (NIV)
1A gentle answer turns away wrath, but a harsh word stirs up anger.
2The tongue of the wise commends knowledge, but the mouth of the fool gushes folly.
3The eyes of the Lord are everywhere, keeping watch on the wicked and the good.
4The tongue that brings healing is a tree of life, but a deceitful tongue crushes the spirit.
Proverbs 12:18 (NIV)
Reckless words pierce like a sword, but the tongue of the wise brings healing.