Contradiction with Jeremiah 5:21
This verse mentions people having eyes and not seeing, and ears and not hearing, which contrasts with Proverbs 20:12 implying that the Lord has made the hearing ear and the seeing eye to perceive correctly.
Jeremiah 5:21: Hear now this, O foolish people, and without understanding; which have eyes, and see not; which have ears, and hear not: [understanding: Heb. heart]
Contradiction with Isaiah 6:9-10
Here, God instructs Isaiah to speak to the people, making their ears dull and their eyes blind, opposing the idea in Proverbs 20:12 that God's creation of ears and eyes is for understanding.
Isaiah 6:9-10: And he said, Go, and tell this people, Hear ye indeed, but understand not; and see ye indeed, but perceive not. [indeed, but understand: or, without ceasing, etc: Heb. in hearing, etc]
Contradiction with Matthew 13:13
Jesus speaks about using parables so that some may not see or hear, contradicting Proverbs 20:12 where the emphasis is on God creating eyes and ears for perception.
Matthew 13:13: Therefore speak I to them in parables: because they seeing see not; and hearing they hear not, neither do they understand.
Contradiction with Ezekiel 12:2
God describes Israel as having eyes that do not see and ears that do not hear, despite the implication in Proverbs 20:12 that He made them for those purposes.
Ezekiel 12:2: Son of man, thou dwellest in the midst of a rebellious house, which have eyes to see, and see not; they have ears to hear, and hear not: for they [are] a rebellious house.
Contradiction with Acts 28:26-27
Paul quotes Isaiah about the people's hearts being calloused, ears dull, and eyes closed, highlighting a discrepancy with the notion of ears and eyes being meant for hearing and seeing as per Proverbs 20:12.
Acts 28:26-27: Saying, Go unto this people, and say, Hearing ye shall hear, and shall not understand; and seeing ye shall see, and not perceive: