PURPORT

"Whenever and wherever there is a decline in religious practice, O descendant of Bharata, and a predominant rise of irreligion-at that time I descend Myself." The Lord appears in each incarnation to save the world from irreligious principles and especially to protect His devotees (paritranaya sadhunam). Vamanadeva, for example, appeared to save the devotee Bali Maharaja. Similarly, when the Supreme Personality of Godhead accepted the abominable form of a fish, He must have done so to favor some devotee. Pariksit Maharaja was eager to know about the devotee for whom the Supreme Lord accepted this form.