For as the medicines which men apply to the bodies of their fellow-men are of no avail except God gives them virtue (who can heal without their aid, though they cannot without His), and yet they are applied; and if it be done from a sense of duty, it is esteemed a work of mercy or benevolence; so the aids of teaching, applied through the instrumentality of man, are of advantage to the soul only when God works to make them of advantage, who could give the gospel to man even without the help or agency of men
All things, even rhetoric and medicine, have effect only through the divine