Romans 12:14
Bless those that persecute, bless and curse not.
Matthew 5:22
But I tell you, that every one who is angry with his brother shall be subject to the judgment; and whoever says to his brother, Worthless fellow, shall be subject to the Sanhedrim; and whoever says, You fool, shall be subject to the hell of fire.
Matthew 5:43-44
You have heard that it was said, You shall love your neighbor, and hate your enemy.
Matthew 12:36
But I tell you, that for every idle word which men speak they shall render an account in a day of judgment;
James 3:6
And the tongue is a fire, the tongue is made a world of wickedness among our members, it defiles the whole body and sets on fire the course of nature and is set on fire by hell.
James 3:9-10
With it bless we the Lord and Father, and with it curse we men made in the likeness of God.
1 Peter 2:22-23
who committed no sin, neither was deceit found in his mouth,
1 Peter 3:9
not returning evil for evil or railing for railing, but on the contrary blessing [your enemies], because to this you are called, that you may inherit blessing.