Jesus claimed to be God in the flesh and to have authority from God to heal, cast out evil spirits and forgive sins. I believe that Jesus backed up his claim to be God by predicting his own death and resurrection. My examination of the historical data leads me to the conclusion that he did indeed die on a Roman cross and did indeed rise from the dead three days later. There is simply no other credible explanation for the events of the time.
So if Jesus really did prove that he was God, then that gives him credibility as the ultimate healer.