Romans 12:14
Bless them that persecute you: bless them, I say, and do not curse them.
Matthew 5:22
but I say unto you, that whosoever is angry with his brother without cause shall be liable to the judgment; and whosoever shall say to his brother, Raca, shall be obnoxious to the council; but whosoever shall say, "Thou fool," shall be in danger of hell-fire.
Matthew 5:43-44
Ye have heard, that it has been said, Thou shalt love thy neighbour, and hate thine enemy:
Matthew 12:36
but I tell you, that of every idle word, which men shall speak, they shall give an account in the day of judgement; for by thy words thou shalt be justified,
James 3:6
And the tongue is a fire, a world of iniquity: so is the tongue among our several parts, defiling the whole body, inflaming the course of nature, and is set on fire by hell.
James 3:9-10
With it we bless God even the Father; and with it we curse men, who are made after the likeness of God:
1 Peter 2:22-23
Who did no sin, neither was guile found in his mouth:
1 Peter 3:9
not returning evil for evil, or reproach for reproach: but on the contrary blessing even those that curse you: knowing ye are called unto this, that ye may obtain a blessing.