deaf and blind, but don't worry, they can still see and hear

In Isaiah 6:9-10 people are referred to as being able to see, but incapable of understanding or believing. This reference can be seen in the healing of Bartimaeus, son of Timaeus (Mark 10: 46-52). Jesus is walking along the road and this blind guy sitting there yelling at Jesus to heal him. Jesus says "What do you want?" The man replies, "I want to see." So Jesus let's him see. Jesus walks off and the man follows him. Bart's physical healing can also be seen as a spiritual healing. Once Bart could physically see, he physically followed Jesus. His following of Jesus is also understood in a spiritual sense. Bart's spiritual eyes had been opened, enabling him to "see" Jesus and follow him.
Jesus also makes reference to understanding in the sense of hearing. In Mark 4 (4 & 23) Jesus tells the crowd that he's teaching, "he who has ears to hear, let him hear." Both of these verses are found in parables that refer to the understanding of spiritual matters. Jesus is telling the crowd in the first parable (the farmer sowing seed) that some people are gonna take things from God and run with them, others won't take things so well, some will not understand. He finished that parable by saying, "Hey, if you are capable of understanding, then understand." The Next parable is about the lampstand, and hiding it under a bushel...no. Um, Anyway, he's referring to God disclosing things about himself to people. If God wants it to be known, he'll make it known. Again, Jesus finishes that up with, "If God shows you something and enables you to understand it, then understand it." Jesus is telling the crowd (disciples and pharisees, too) that they're walking around with their fingers in their ears. He's inviting them to open up their spiritual senses and understand what God's put in front of them.

Alex H