This Bible contradiction is from the Skeptic's Annotated Bible.
It's OK to call someone a fool.
Psalm 14:1 View context
The fool hath said in his heart, [There is] no God. They are corrupt, they have done abominable works, [there is] none that doeth good.
Psalm 53:1 View context
The fool hath said in his heart, [There is] no God. Corrupt are they, and have done abominable iniquity: [there is] none that doeth good.
Proverbs 28;26 View context
Matthew 23:17 View context
[Ye] fools and blind: for whether is greater, the gold, or the temple that sanctifieth the gold?
Luke 11:40 View context
[Ye] fools, did not he that made that which is without make that which is within also?
Luke 24:25 View context
Then he said unto them, O fools, and slow of heart to believe all that the prophets have spoken:
Romans 1:21-22 View context
Because that, when they knew God, they glorified [him] not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.
Professing themselves to be wise, they became fools,
1 Corinthians 15:36 View context
[Thou] fool, that which thou sowest is not quickened, except it die:
Galatians 3:1 View context
O foolish Galatians, who hath bewitched you, that ye should not obey the truth, before whose eyes Jesus Christ hath been evidently set forth, crucified among you?
It's not OK to call someone a fool.
Matthew 5:22 View context
But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.