God cannot be possessed. If we try to do this, the in the words of Martin Buber: "Whoever is converted by substitution, now has a phantom he calls God. God, however, the eternal presence, cannot be had. Woe unto the possessed who fancy they possess God."
For as Buber asserts, the problem is not merely the object, the idol itself that is the problem, but also the way one relates to the idol.
For instance, if one idolizes women, merely replacing women with God does nothing to change the, what I would suggest is sinful, way one related to women - treating them as objects merely to satisfy an sexual desire, not as humans. Or if one idolizes money because of the status it affords or the pleasures it can buy, then substitutes God for money, the heart is not changed. Rather one takes up a new means to try and accomplish that which I hoped to do with money.So then God becomes a phantom. We like the idea of God because of what he can do for us. And the way in which we attempt to relate to the Divine Creator of the universe (as the substitute for our idol) is still bent towards our utilitarian purposes.
Thus, casting aside our idols involves changing the way we relate to objects in addition to relinquishing the objects of our idolatry. Not only the object changes, but also the way we attempt to relate.
Another way to think of it is this. Let's say I have a sudden stroke of conscience and recognize the need to get rid of my gas-guzzling car in order to do my part to save the environment. Do I trade-in or substitute my old car for on a better, new car that still guzzles gas? Or Do I get rid of the car entirely and begin riding a bicycle? One is substitution. The other is life-change.
I can't help but think of Paul's words in 2 Corinthians about being a new creation in Christ. "If anyone is in Christ, he is a NEW CREATION, the old has gone the new has come." (2 Cor 5:17, emphasis added.)
Rather than making God a phantom through substituting objects, transformation occurs. We are completely new. Our idols are cast aside as well as the bent ways in which we attempt to relate to those objects. In their place comes a life-giving, whole-person renewing relationship with God. And we begin to learn to relate to all objects rightly - the way God intended.