Now a leper came to Him, imploring Him, kneeling down to Him and saying to Him, “If You are willing, You can make me clean.” Then Jesus, moved with compassion, stretched out His hand and touched him, and said to him, “I am willing; be cleansed.” As soon as He had spoken, immediately the leprosy left him, and he was cleansed. And He strictly warned him and sent him away at once, and said to him, “See that you say nothing to anyone; but go your way, show yourself to the priest, and offer for your cleansing those things which Moses commanded, as a testimony to them.”— Mark 1:40-44 NKJV
These verses show the balance of scriptural healing. First, the attitude is “If You are willing L-RD.” The leper had no doubt in his mind, no lack of faith, in the ability of Jesus’ power. However, he did understand the sovereignty of G-d.
Second, when the healing comes, you are to say nothing to anyone and get it confirmed. In that day and culture a healing was confirmed by a priest. Today, we get ailments and see doctors. A healing of those ailments are to be confirmed by the doctor. This act is scriptural, as it allows for G-d to be glorified through the testimony of His work. The confirmation by the doctor, as done by the priest in those days, is a validation of the power of G-d. It is not a lack of faith as some teach, but rather an opportunity for G-d to be glorified through that official confirmation that a healing has definitely taken place.