Healing is a work of the gospel. Signs follow the un-seen work of God to show inwardly in the person heart a person heard the "gospel of faith" and as a witness they believe God .
Its not a work of man. The apostle were witness to the work of God. God uses specific healing to represent the work of the gospel .
Like for instance the one in Acts 14
And there they
preached the gospel. And there sat a certain man at Lystra, impotent in his feet, being a
cripple from his mother's womb, who
never had walked:The same heard Paul speak: who stedfastly beholding him, and perceiving that he
had faith to be healed, Said with a loud voice, Stand upright on thy feet. And he leaped
and walked.And when the people saw what Paul had done, they lifted up their voices, saying in the speech of Lycaonia, The gods are come down to us in the likeness of men. Acts14:7-11
Those who walked by sigh having not faith made the apostles into gods in the likeness of men ,Again having nothing to do with the Apostle
The
faith he had heighted in the verse to be healed was not himself . It enables him to walk or understand God not seen . Lame is one of the metaphors used in parables to show a person believes God.
A another example in when John the Baptist had some doubt if Christ was the one to represent the gospel . using the same metaphors in other parables .
blind see..... spiritually
lame walk..... walk by their new faith
the lepers are cleansed...… restoring from the dead
the deaf hear......Given the hearing of faith that come through the word of God needed to believe God not of their own mind
the dead are raised...….the first resurrection. when we belive God.
They are all gospel metaphors that show they have become a new creation.
Altogether uses those same metaphors throughout the Bible as a witness to the poor (spiritually bankrupt) the gospel was preached. The focus is never in respect to the temporal healing. But rather the gospel is the focus.
Luke 7:22 Then Jesus answering said unto them, Go your way, and
tell John what things ye have seen and heard; how that the
blind see, the lame walk, the lepers are cleansed, the deaf hear, the dead are raised, to the poor the gospel is preached.