The way I would define healing is this—it is when someone who is sick is restored to health, not through the use of any medicine, but instead, depending on the power of the God that is flowing through a believer.
Let me just elaborate on this definition of mine a bit.
First, God uses believers as His instruments to heal those who are sick. When I use the term “believer,” I mean someone who believes in Jesus. And by believing, it is not just a moral assent or having head knowledge about it, but trusting that indeed God can and does heal.
Second, the source of this healing is God. It is not from any man or woman who may be moving in the ministry of healing. Ultimately, every single one of these healing ministers will have to acknowledge that every ounce of healing anointing that flows through them is from God. Just as the prophet Zechariah declared, ‘Not by might nor by power, but by my Spirit,’ says the LORD Almighty (Zechariah 4:6).
Third, this healing happens through the intervention of God, without using any natural means of help, such as medicine or some other medical procedures. I know that God can and does bless the science of medicine and bring about healing through it. But this healing that I am talking about is that which depends solely on the ability of God to heal supernaturally.
And fourth, the end point of this healing is that the sick person is restored to his health.
(excerpted from chapter 1 of Healing Is Yours)