When Worship In the Name of God Becomes Idolatrous – Part 1

Luther:  IDOLATRY AMONG THE JEWS

Moreover since the prophets cry out most of all against idolatry, it is necessary to know the form which this idolatry took. In our time … many people are flattering themselves pleasantly, imagining that they themselves are not idolaters like the children of Israel. This is also why they think disparagingly of the prophets—especially of this part of their message in which they rebuke idolatry—as not being applicable to them. These people are far too pure and holy to commit idolatry, and it would be ridiculous for them to be afraid or terrified because of threats and denunciations against idolatry. But that is the very same thing the people of Israel did. They simply would not believe that they were idolatrous; the threatenings of the prophets therefore had to appear as lies, and the prophets themselves had to be condemned as heretics.
The children of Israel were not such mad saints as to worship mere wood and stone. This was especially true of the kings, princes, priests, and prophets, and yet they were the most idolatrous of all. Their idolatry, however, consisted in letting go of the worship which had been instituted and ordered at Jerusalem—and wherever else God would have it—and of trying to do it better somewhere else. They instituted and established it elsewhere, out of their own notions and opinions, and without God’s command. They concocted new forms and persons and times for worship, even though Moses had strictly forbidden this, especially in Deuteronomy 12[:4, 8, 28, 32] and was always pointing them to the place that God had chosen for his tent and tabernacle [Deut. 12:5, 11, 13–14, 17–18, 21, 26]. This false thinking was their idolatry. Yet they regarded it as a fine and precious thing and relied upon it as if they had done it well, though it was outright disobedience and apostasy from God and his commands.
So we read in I Kings 12[:28] that Jeroboam not only set up the two calves, but in addition had it preached to the people, “You shall no longer go up to Jerusalem; behold instead, Israel, here is your God, who brought you up out of Egypt.” He does not say, “Behold, Israel, here is a calf,” but, “Here is your God who brought you up out of Egypt.” He confesses freely that the God of Israel is the true God and that he brought them up out of Egypt; yet men need not run to Jerusalem after him, but can find him all right here in Dan and Beersheba,85 where the golden calves are. This is really the meaning: One can sacrifice to God and worship him as well before the golden calves—as a holy symbol of God—as men sacrificed to him and worshiped him before the golden ark at Jerusalem. This, then, is to desert the worship of God at Jerusalem and thereby to deny the God who commanded such worship, as if he had not commanded it. Thus the people of Israel built on their own works and opinions, and not solely on God alone.
With this thinking they subsequently filled the land with idolatry. Whoever said differently was a heretic and a false prophet. This is the real committing of idolatry, to set up a form of divine worship and service without God’s bidding, simply out of one’s own pious inclination. For God will not have us teach him how he is to be served. He wills to teach us and to prescribe for us. His word is supposed to be there; it is supposed to enlighten and guide us. Without his word all is idolatry and outright lies, however devout and beautiful it may appear to be.

Martin Luther, Vol. 35: Luther's works, vol. 35 : Word and Sacrament I (35:268).

Part 2   Luther:  Idolatry Among Christians