Therefore the holy church cannot and may not lie or suffer false doctrine, but must teach nothing except what is holy and true, that is, God’s word alone; and where it teaches a lie it is idolatrous and the whore-church of the devil. What help was it to the kings of Israel to boast that they served the God of Israel, who had led them out of Egypt? Indeed, they sought and called on the true God of their fathers, and they also held the law of Moses. But since, in addition, they honored calves and Baal, or at least instituted their own new worship in honor of the true God in their religious fervor, they lost everything. For God’s command, “You shall have no other God before me” [Deut. 5:7], stood against this; and Deuteronomy 4 [:2] and 12 [:32] had strongly forbidden them to undertake anything new or different on their own, saying, “You shall not add to the word which I command you, nor take from it.” And again, “You shall not turn aside to the right hand or to the left” [Deut. 5:32], that is, to make it better or worse, to limit or to change it. Therefore we read everywhere in the prophets how they rebuke the kings, priests, and people for always inventing new ways and not remaining on the one and only path. (Luther’s Works, v.41, p.214)
Picture: The altar at History Trinity Lutheran Church, Souland Market, St. Louis MO