Now the work of healing or preserving is not proper to man, but to God. So again, in the law it says, “Thou shalt not do any manner of work in it,” except what is to be done for any soul, that is to say, in the matter of delivering the soul; because what is God’s work may be done by human agency for the salvation of the soul. By God, however, would that be done which the man Christ was to do, for He was likewise God.
Tertullian
The Five Books Against Marcion, Book IV
Chapter XII