There are two kinds of supreme purity. When one type is possessed, one is able to deliver a sinful person. When the other type is possessed, one does not do anything which is impure. A person who possesses either of these qualities is called supremely pure. Krsna is both; He can deliver all sinful conditioned souls, and at the same time, He never does anything by which He can be contaminated.
In this connection, Vidura, while trying to detach his elder brother, Dhrtarastra, from his familial attachments, said, "My dear brother, you just fix your mind on the lotus feet of Krsna, who is worshiped with beautiful erudite verses by great sages and saintly persons. Krsna is the supreme deliverer amongst all other deliverers. Undoubtedly there are great demigods like Lord Siva and Lord Brahma, but their positions as deliverers depend always upon the mercy of Krsna." Therefore Vidura advised his elder brother Dhrtarastra to concentrate his mind and worship only Krsna. If one simply chants the holy name of Krsna, this holy name will rise within one's heart like the powerful sun and will immediately dissipate all the darkness of ignorance. Vidura advised Dhrtarastra to therefore think always of Krsna so that the volumes of contaminations due to sinful activities would be washed off immediately. In the Bhagavad-gita also Krsna is addressed by Arjuna as param brahma param dhama pavitram [Bg. 10.12]-the supreme pure. There are many other instances exhibiting Krsna's supreme purity.

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