He therefore that ministereth to you the Spirit, and worketh miracles among you, [doeth he it] by the works of the law, or by the hearing of faith?
Note 9 at Ga 3:5: It doesn't matter if the "he" in this verse was Paul or someone else. The point he was making is that those who are used of God don't deserve it. The Lord has never had anyone qualified working for Him yet (see note 8 at Ro 9:16). It's God's grace that He uses anybody. Those who claim to be used of God because of their great holiness are either deceived or deceiving. It's faith in the grace of God that allows miracles to flow through people.