Exodus 4:11 Then the Lord said to him, “Who has made man's mouth? Who makes him mute, or deaf, or seeing, or blind? Is it not I, the Lord?"

In Chapter 4 of Exodus God takes responsibility for making people deaf, dumb, or blind. If God intended them to be disabled, why do we attempt to heal them with our modern treatments. Does this subvert his purpose? Why would God want to make someone disabled in the first place? If disabilities are a result of Original Sin, why are some people disproportionately affected, even from birth, with terrible disabilities? If God is good and can control who is sticken with disabilities, why doesn't he ever heal them? Some claim that God does heal the sick and disabled, not just in the past, but still to this day through the power of prayer. If that is the case, why are there some types of disability that have seemingly never been miraculously healed? For instance, why doesn't God heal amputees?