Contradiction with Proverbs 20:12
This verse speaks of the Lord giving both hearing ears and seeing eyes, which contrasts with Isaiah 42:18's reference to the absence of these abilities.
Proverbs 20:12: The hearing ear, and the seeing eye, the LORD hath made even both of them.
Contradiction with Matthew 13:16
Matthew records that those who follow Christ have blessed eyes and ears because they see and hear, contradicting the emphasis on blindness and deafness in Isaiah 42:18.
Matthew 13:16: But blessed [are] your eyes, for they see: and your ears, for they hear.
Contradiction with Romans 11:8
This verse notes that God gave people a spirit of stupor, eyes that should not see and ears that they should not hear, which seems to affirm rather than contradict, showing God's control, differing from the call to awareness in Isaiah 42:18.
Romans 11:8: (According as it is written, God hath given them the spirit of slumber, eyes that they should not see, and ears that they should not hear;) unto this day. [slumber: or, remorse]
Contradiction with John 9:39
Jesus claims that he came so the blind would see and those who see would become blind. It offers a different view on spiritual sight and blindness compared to Isaiah 42:18.
John 9:39: And Jesus said, For judgment I am come into this world, that they which see not might see; and that they which see might be made blind.