Purport

This is one of the most important Shlokas of Shrimad Bhagvad Gita and gives a direct answer to why Idol worship is not only important but a necessity for worship.

As explained in earlier Shlokas, Arjuna now realized Shri Krishna is none other than the God almighty. Hearing the glory as revealed, he accepted nobody can know the true nature of Bhagvan Shri Krishna, neither deities nor Danavas or human.

But then here comes the real question, which he is now asking Shri Krishna. How a human can worship Shri Krishna then?
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As Shri Krishan explained himself, he is absolute, infinite, all-pervading and omnipotent. But truly speaking can any of these attributes be comprehended by a human? the answer is no. These are all absolute attributes, way beyond the capacity of the human brain to comprehend. How a human can understand an infinite? What sort of things might go to the human mind when he tries to understand omnipotent.

The summary if that human can never understand or comprehend absolute attributes which God posses. Then the question arises, how a human can worship that God which he can't understand? worshipping God without understanding is as a blind walking randomly thinking he may reach to correct destination.

Now here comes the required of a finite form, symbol or to say idol. A finite form is what humans can see and can understand. Once he understands the form, he automatically connects to that form and what is how he can worship God. This worship is what called idol worship.

After this Shloka Bhagvan Shri Krishna then explains his finite forms to Arjuna. Finite forms of Shri Krishna is what called as Vibhuti, This chapter hence is called as Vibhuti Yoga.