“This is all the old devil and old snake, who also tuned Adam and Eve into enthusiasts and led them from the eternal Word of God to “spirituality” and their own presumption… In short: enthusiasm clings to Adam and his children from the beginning to the end of the world – fed and spread among them as poison by the old dragon. It is the source, power, and might of all the heresies, even that of the papacy and Mohammed. Therefore we should and must insist that God does not want to deal with us human beings, except by means of his external Word and sacrament. Everything that boasts of being from the Spirit apart from such a Word and sacrament is of the devil.”

– Martin Luther, “Smalcald Articles”  (3.8)