“What is it to have a god? What is God? Answer: A god is that to which we look for all good and in which we find refuge in every time of need. To have a god is nothing else than to trust and believe him with our whole heart. As I have often said, the trust and faith of the heart alone make both God and an idol. If your faith and trust are right, then your God is the true God. On the other hand, if your trust is false and wrong, then you have not the true God. For these two belong together, faith and God. That to which your heart clings and entrusts itself is, I say, really your God.”
Martin Luther, The Large Catechism (Philadelphia, 1959), page 9.
If follows that one can worship a false god, with destructive impact, without intending to or even realizing it. Converting to Christ introduces us not only to him but also to ourselves and the false trusts/gods that lurk in our self-evident thoughts and natural feelings.
(HT: Ray Ortlund)