Deafness means not being able to hear. In the Bible, it can mean not being able to hear with your ears or not being able to hear in your spirit. The spiritually deaf were those who either refused to hear God's message or were not able to because of their lack of spirituality (Isaiah 42:18).
The prophet Isaiah speaks strongly about both types of deaf people. Isaiah talks about the spiritually deaf in Isaiah 42:18; 43:8. Isaiah talks about the actual deaf in Isaiah 29:18; 35:5. The Old Testament speaks of not being able to hear as the result of God’s judgment (Micah 7:16). It also says it is wrong to curse a deaf person (Leviticus 19:14).
In the New Testament, Jesus healed the deaf (Matthew 11:5; Mark 7:32–37; Luke 7:22). In Mark 9:25, Jesus healed a boy who had a “deaf and mute spirit." These healings were evidence of Jesus’s role as Messiah.