Srila Bhaktivinoda Thakura in his Sri Caitanya Siksamrita describes the demons Krishna killed in His Vrindavana pastimes and the anarthas (unwanted things) that they represent.
1. Putana - the pseudo guru.
2. Sakatasura (the cart demon) - carrying the burden of a cart-load of old and new bad habits, lethargy and vanity.
3. Trinavarta (the whirlwind demon) - false pride that comes from material scholarship, which leads to bogus philosophies.
4. Deliverance of Nalakuvara and Manigriva (breaking the twin arjuna trees) - Arrogant pride that comes from puffed-up prestige, which is rooted in madness for wealth.
5. Vatsasura (the calf demon) - a childish type of mentality which gives rise to a type of greediness, which results in a wicked type of mischievousness.
6. Bakasura (stork demon) - Cunning duplicity, deceptiveness and false types of behavior.
7. Aghasura (the snake demon) - Cruelty and violence.
8. Brahma-vimohana Pastime (Lord Brahma steals the cowherd boys and calves) - mundane activities and speculative scholasticism.
9. Dhenukasura (the ass demon) - gross materialistic intelligence, ignorance of spiritual knowledge.
10. Kaliya (chastising the Kaliya serpent) - brutality and treachery.
11. Extinguishing the Forest Fire - inter-communal discord among Vaishnavas.
12. Pralambasura (killing the Pralamba demon) - lusty inclinations; desire for personal gain and honor.
13. Second Forest Fire - disturbance of religious principles and interference with religious people who are atheist.
14. Brahmanas Performing Sacrifice - indifference toward Krishna caused by pride because of one’s status (position) in varnasrama.
15. Overcoming the Pride of Indra - demigod worship, and the tendency to think, “I am Supreme.”
16. Nanda Maharaja Captured by Varuna - thinking that spiritual life can be enhanced by intoxication.
17. Nanda Maharaja Swallowed by Vidyadhara (the snake) - rescuing the truth of Krishna consciousness from being swallowed by the impersonalists.
18. Sankhacuda (killing the conch-shell demon and getting the jewel that was stolen by him) - proneness toward acquiring name and fame, and desire for sensuous enjoyment, under the plea of devotion.
19. Aristasura (the bull demon) - pride arising from indulging in false religions invented by cheaters which causes neglect of devotional service (bhakti).
20. Kesi (the horse demon) - The feeling that “I am a great devotee and spiritual master.”
21. Vyomasura (the demon in the sky) - associating with thieves and other rascals, and with people who put themselves forward as avataras.
Bhaktivinoda Thakura says: “The devotee who worships the holy name should first petition the Lord for the strength to cast out all these unfavorable tendencies—and should pray thus before Lord Hari on a daily basis. By doing this regularly, the devotee’s heart will eventually become purified. Sri Krishna has killed a number of demons which may arise in the kingdom of the heart—so in order to destroy these problems, a devotee must cry very humbly before the Lord and admit defeat—then the Lord will nullify all contaminations.”
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