Too often we are tempted to turn and worship the icon, and that is idolatry. The golden calf of the Israelites In the wilderness is the prototypical idol, the man-made creature which was worshiped instead of the Creator, dead metal rather than Living Maker.
After the flight from Egypt, the amazing journey through the Red Sea, the long years of trekking towards the Promised Land, Moses was over-long talking with God, and the impatient and anxious people felt abandoned both by Moses and God. They said to Aaron, "Up, make us gods, which shall go before us; as for this Moses, the man that brought us up out of the land of Egypt, we know not what is become of him."
And Aaron (what was he thinking of? We would have expected better of him!) said unto them, "Break off the golden earrings, which are In the ears of your wives, and of your sons, and of your daughters, and bring them unto me." And Aaron melted down all the jewelry which was given him and made a golden calf, and "He built an altar before it."
Aaron and the people did what God had clearly forbidden: "They made a calf in Horeb, and worshiped the molten image. Thus they turned their glory into the similitude of a calf that eats hay" They tried to turn their idol into a god and of course it did not work; it never does.
And Moses, coming down from the mountain after talking with God, saw the golden calf and the people dancing around it, and he was furious, and told Aaron so in no uncertain terms. Aaron defended himself, explaining that the people wanted gods to go with them, and they didn't know where Moses was, so Aaron took their gold, and threw it into the fire, and "Out came this calf"! Rationalizing and alibi-ing, just as we still do today: Who, me? I had nothing to do with it. Out came this calf!
An icon does not have to be an idol. An icon should give us glimpses of our God who is both immanent and transcendent, knowable and unknowable. If an icon becomes more important to us than what it reveals of God, then it becomes a golden calf, but this does not need to happen.
-- Madeleine L'Engle in Penguins and Golden Calves