The Israelites even offered their firstborn children as sacrifices to the god Molech. This was a terrible sin.
This action reversed what God had done in the exodus. At that time, the Lord called Israel his “firstborn son” (Exodus 4:22). He rescued them from slavery so they could worship him in purity in the promised land.
Instead of honoring the Lord, they gave their children to a false god. Their actions showed how far they had turned away from him.