Most people want some objective thing: material that they want to sanctify and worship: therefore, this is the basis of the idolatry.
Most people do not believe in God unless they associate others beside Him, so this is the basis of the idolatry and the enthusiasm about their religious men and chiefs lead them (by the persuasion of Satan) to sanctify the religious men and the chiefs ... so as to fall in the idolatry or the association with God.
An incident:
When the children of Israel crossed the sea together with Moses ... by a miracle that was so marvelous and they saw with their own eyes the drowning of Pharaoh and his host ... they came to pass by a people worshiping some idols, and the children of Israel said to Moses: Assign to us some idols which we may worship like these people worshiping their idols.
Moses was surprised: he said to them: How can I assign to you any god other than God Almighty Who has just saved you and drowned your enemy!?
A similar incident occurred in the time of Prophet Mohammed:
People came to pass by a tree which the idolaters used to sanctify and seek blessing by taking some bands of clothes, tying them to that tree then tying such bands to their weapons.
They said: God's messenger, assign for us a tree like this so that we may take bands to our weapons!
The Prophet cried: Allahu Akbar! Such was the doing of the past nations before you; this is what the children of Israel demanded of their prophet Moses. (And in his absence they worshiped the statue of the gold calf.)
This is in the Quran 7: 138-139, which mean:
{138. And We took the children of Israel across the sea a, and they came to a people who were devoted to some idols which they had.
The [children of Israel] said: "O Moses, make for us a god b, even as they have gods c." [Moses] said: "You are surely a people ignorant [about God and His might.]"
139. "Certainly, the work d of these [idolaters] will lead to destruction e, and all that they are doing is in vain f."
140. [Moses] said: "Shall I seek for you a god other than God when He has favored you [with excess bounties and surplus] above all peoples of the world?"}
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a i.e. We made for them a road in it, and they crossed.
b Which we should worship.
c Which they worship.
d i.e. the idol worship.
e It means: they are going to be destroyed because of such act of theirs.
f They will not be rewarded for it, but will be punished and will lose.
The interpretation is by Mohammed-Ali Hassan Al-Hilly.
