Isaiah 44:13-20 The carpenter measures with a line and makes an outline with a marker; he roughs it out with chisels and marks it with compasses. He shapes it in the form of man, of man in all his glory, that it may dwell in a shrine. He cut down cedars, or perhaps took a cypress or oak. He let it grow among the trees of the forest, or planted a pine, and the rain made it grow. It is man’s fuel for burning; some of it he takes and warms himself, he kindles a fire and bakes bread. But he also fashions a god and worships it; he makes an idol and bows down to it. Half of the wood he burns in the fire; over it he prepares his meal, he roasts his meat and eats his fill. He also warms himself and says, "Ah! I am warm; I see the fire." From the rest he makes a god, his idol; he bows down to it and worships. He prays to it and says, "Save me; you are my god." They know nothing, they understand nothing; their eyes are plastered over so they cannot see, and their minds closed so they cannot understand. No one stops to think, no one has the knowledge or understanding to say, "Half of it I used for fuel; I even baked bread over its coals, I roasted meat and I ate. Shall I make a detestable thing from what is left? Shall I bow down to a block of wood?" He feeds on ashes, a deluded heart misleads him; he cannot save himself, or say, "Is not this thing in my right hand a lie?"
So is it idolatry if one makes a wooden cross, for example, and assumes that the real presence of God is in the object, believing that God transubstantiates Himself into the wooden object, the wooden cross itself becoming God to that person, and so worships the wooden object which to them is God?
Is it idolatry only to the person who doesn't believe in the real presence of God in the object? Should the person who doesn't believe that God has transubstantiated Himself into the object consider the person who does believe such to be an idolator?
And does the Isaiah passage above apply?
