What is an Idol?

I would like to take a break from 1st Timothy for a second to discuss a little future Th.M topic. Toby from Classical Presbyterian has challenged me to make the case that a stained glass image that is supposed to represent Jesus is the equivalent of worshiping an idol. However before I begin that I do want to say as with the discussion we had over the use of musical instruments, the fathers of the Reformed Faith are unequivocally on my side (not to say that Toby has a side). Just one medium snippet from John Calvin shows this:

Idolaters in vain endeavor to elude this second point (Deut 5:8-9) by their foolish cavils; as amongst the Papists that trifling distinction is commonly advanced, that only λατρέια, and not δελέια is prohibited. For Moses, first of all, comprehends generally all the Forms And Ceremonies Of Worship; and then adds immediately afterwards the word עבד, gnabad, which means properly to serve. Hence we conclude that they make a childish endeavor at evasion, when they pay only the honor of service to pictures and statues. But if we grant them what they desire, not even so will they escape; because the prohibition is equivalent to God’s declaring that He will not be worshiped in wood and stone, or in any other likeness. For unbelievers have never been carried away to such an extent of folly as to adore mere statues or pictures; they have always alleged the same pretext which now-a-days is rife in the mouths of the Papists, viz., that not the image itself was actually worshiped, but that which it represented. But the Spirit everywhere reproves them for worshiping gods of wood and stone, since God rejects that carnal worship which unbelievers offer before stocks and stones. If any one should ask them, whom they have it in their mind to worship, they will immediately reply, that they offer to God that honor which they pay to pictures and statues. But this frivolous excuse comes to nothing; because to erect the idol before which they prostrate themselves, is really to deny the true God; and, therefore, no wonder that He should declare that unbelievers worship wood and stone, when they worship in that wood and stone phantoms of their own imagination. And we have already said, that all rites which do not accord with the spiritual worship of God, are here forbidden: and this is enough, and more than enough to put to flight all such misty notions, (nebulas.)...But if it be not agreeable to our judgment that God should repay every one according to his deserts, and yet that He at the same time requires the sins of their fathers of the children, we should remember that His judgments are a great depth; and, therefore, if anything in His dealings is incomprehensible to us, we must bow to it with sobriety and reverence.

One could at this point say well we are not Roman Catholics or the Eastern Orthodox and we do not offer prayers to the images of Christ or other fleshly beings in mediation that plaster our sanctuaries, and you would be right to say that. However it would not be right to say that praying is all that we do in the worship of God or that stain glass images of Christ cannot become idols of worship to people in the sanctuary. We deceive ourselves if we say that the images of the 12th Century Danish sculptor that adorn our walls dressed in a toga standing in for Jesus can in the least bit be taken seriously. Why would it even make sense for half-a-second to us to place a fake Jesus on the decor of the house of God? Would we tolerate placing a triangle in place of a cross? So why does it not bother us to place the picture of a sinful human in place of Christ, even if we are "worshiping" it? So even before we get into any real discussion of whether or not this false Christ can equal an idol we must first think about whether it is prudent to give people a false impression of what Christ looked like in the flesh. If we consider this I think we have the answer to our idolatry question already.