Because there's a difference between God and gods. The former is the source of the Christian faith, the latter is any idolatry given to any symbol or person.
@MetalGreymon I don't know. I didn't write the bloody book did I. But the passage is about worshipping human things the way God is worshipped. I think it's s warning against charlatans and posers.
I guess it depends how you look at it. There do seem to be several references to there being a number of gods in the bible. And that would make this prohibition more useful.
After all, who is going to worship a statue when there is a god actually giving blessings or ( more often) wreaking great destruction ?
@MetalGreymon Worshipping of statues is not really worshipping or idolatry. It's simply using a visual, tactical representation to pay respect to the person it represents. Not worshipping of the actual object.
Well sure, but the point stands. Why would they be worshiping something that doesn't exist and has therefore never done anything when there is a god like OT god around?
Well you pointed out that worshiping an idol is just worshiping what that idol represents, which is true. But that still doesn't get us any closer to the answer. Why would anyone worship a god that doesn't exist when there is such an active god around?