A survey conducted by the American Academy of Family Physicians shows that 99% of doctors believe a relationship exists between faith and physical healing. Recently, more than 1,000 health-care professionals met at Harvard Medical School to examine the connection between spirituality and healing. Doctors’ faith in faith was bolstered by a California study of the effect of prayer on recovery from heart problems. About two hundred heart patients were assigned to Christians who prayed for them, while an equal number, a control group, received no known prayers. Neither group knew about the prayers, yet those who received prayer developed half the complications that were experienced by those in the control group. A similar study by the Dartmouth Medical School examined the effect of prayer on healing when the patients prayed for themselves. The death rate six months after bypass surgery was 9 percent for the general population but 5 percent for those who prayed for their own healing. And none of the deeply religious patients died during the period of the study. (The Associated Press, quoted in “Religion in the News,” Signs of the Times, March 1997, p. 4)
For centuries people have exercised their faith and seen God do the miraculous. Great healing, restoring families, provisions coming just when they are needed, and lives genuinely changed by Holy Spirit have all happened for people of prayer and faith.
I have heard before,”What if I do this faith thing and nothing happens? My response is usually,”What if you do this faith thing and something does happen. I mean what have you got to loose? Your reputation for trusting God?” In the bible there is a chapter often called "Faith’s Hall of Fame". It is a list of men and women who exercised faith and were rewarded.
Hebrews 11:33-35a [these men and women] who through faith subdued kingdoms, worked righteousness, obtained promises, stopped the mouths of lions,  quenched the violence of fire, escaped the edge of the sword, out of weakness were made strong, became valiant in battle, turned to flight the armies of the aliens...
God is not a respecter of persons, but He is a respecter of a person’s faith. He gives to those who exercise their faith. Jesus said “All things are possible to him who believes.” Quite an amazing statement. What is the criteria? To him who believes.