We must take note that God's ability to heal is not based on a correct or incorrect model. It is built on his compassion to make right what is wrong in his world. The worldview you hold determines the way you believe and view Scripture and everything else for that matter. We all operate within a worldview often without being conscious that we are doing so. We assume that the way we view life is the way everyone views life.
Unanswered questions can often immobilize a person with fear.
Often the fear comes from not being equipped to answer hard questions, not only for ourselves but for the ones to whom we are sent to minister. The Old Testament is not the first place that a Christian turns to study the concept of healing. It is often not even the last place. For many Christians the Old Testament is a dusty old book that sounds really ancient. By the time we open the pages of the New Testament we can see a change in the way these folks were beginning to think about evil.