What is a kanistha adhikari?
In the eleventh canto it is mentioned. He is fond of worshipping only the deity. And the deity has some Bhaktas. The deity has some devotees those who are serving Him. He is not careful of honoring them. And also in those who are not devotees, he cannot see any Divinity in them. There is nothing special about them. Everything else other than the deity is ordinary. So, such a devotee is called prakrata Bhakta, which is coming from the word Prakrti. So, he cannot see any Divinity in Prakrti. So he is an ordinary person. Hence known as Prakrta Bhakta.

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