According to Bhagavad-gita, a sadhu (holyman) is a man in Krsna consciousness. A person may appear to be irreligious, but if he has the qualifications of Krsna consciousness wholly and fully, he is to be understood to be a sadhu. And duskrtam applies to one who doesn't care for Krsna consciousness. Such miscreants, or duskrtam, are described as foolish and the lowest of mankind, even though they may be decorated with mundane education; whereas another person, who is one hundred percent engaged in Krsna consciousness, is accepted as sadhu, even though such a person may neither be learned nor well cultured. As far as the atheistic are concerned, it is not necessary for the Supreme Lord to appear as He is to destroy them, as He did with the demons Ravana and Kamsa. The Lord has many agents who are quite competent to vanquish demons. But the Lord especially descends to appease His unalloyed devotees, who are always harassed by the demonic. The demon harasses the devotee, even though the latter may happen to be his kin. Although Prahlada Maharaja was the son of Hiranyakasipu, he was nonetheless persecuted by his father; although Devaki, the mother of Krsna, was the sister of Kamsa, she and her husband Vasudeva were persecuted only because Krsna was to be born of them. So Lord Krsna appeared primarily to deliver Devaki, rather than kill Kamsa, but both were performed simultaneously. Therefore it is said here that to deliver the devotee and vanquish the demon miscreants, the Lord appears in different incarnations.

There are various kinds of avataras, such as purusavataras, gunavataras, lilavataras, saktyavesa avataras, manvantara-avataras and yugavataras—all appearing on schedule all over the universe. But Lord Krsna is the primeval Lord, the fountainhead of all avataras. Lord Sri Krsna descends for the specific purposes of mitigating the anxieties of the pure devotees, who are very anxious to see Him in His original Vrndavana pastimes. Therefore, the prime purpose of the Krsna avatara is to satisfy His unalloyed devotees.