“I am the Lord your God, who rescued you from the land of Egypt, the place of your slavery. You must not have any other god but me.”
“You must not make for yourself an idol of any kind, or an image of anything in the heavens or on the earth or in the sea. You must not bow down to them or worship them, for I, the Lord your God, am a jealous God who will not tolerate your affection for any other gods. I lay the sins of the parents upon their children; the entire family is affected—even children in the third and fourth generations of those who reject me. But I lavish unfailing love for a thousand generations on those who love me and obey my commands.” (NLT)
When people tell us they believe in God, it doesn’t tell us much. That word “God” can mean different things to different people. When the God of the Bible gave his commands to his people, he was telling them he was the only one. The others were dangerous fantasies. Worship of a deity was not a matter of picking our favourite God from a supermarket shelf.
He warns against idolatry which has been described as worshipping something that should be used, and using something that should be worshipped. So we may give ultimate value to money or sex or power which are fair enough servants but unwise masters. And so we use the one true God to achieve our own self-centred goals. Each is idolatry.
Nowadays, we won’t likely construct a physical idol and literally bow down before it. But we can cultivate false imaginings of our God. We imagine him to be an indulgent granddad or a tyrannical despot. We twist him so that we create him in our own image. This too is idolatry.
Get God wrong and everything else becomes distorted when it comes to faith. See him as a means to an end rather than an end in himself is to get him wrong. See him as a projection of all our private wishes and we get him wrong. By all means call yourself a believer in God. But be pretty clear on what God it is that you believe in.