Matthew 5:21-22

Ye have heard that it was said to the ancients, Thou shalt not kill; but whosoever shall kill shall be subject to the judgment. But I say unto you, that every one that is lightly angry with his brother shall be subject to the judgment; but whosoever shall say to his brother, Raca, shall be subject to be called before the sanhedrim; but whosoever shall say, Fool, shall be subject to the penalty of the hell of fire.