nijamsa-kalaya krsna tamo-guna angikari'
samhararthe maya-sange rudra-rupa dhari
nija-amsa—of His personal plenary expansion; kalaya—by an expansion known as kala; krsna—Lord Krsna; tamah-guna—the material mode of darkness; angikari'-accepting; samhara-arthe—for the purpose of dissolution; maya-sange—in association with the external energy; rudra-rupa—the form of Rudra; dhari—assumes.
"Lord Krsna, the Supreme Personality of Godhead, expands a portion of His plenary portion and, accepting the association of the material mode of ignorance, assumes the form of Rudra to dissolve the cosmic manifestation.
This is a description of the Rudra form, which is another expansion of Krsna. Only visnu-murtis are expansions of Krsna's personal and plenary portions. Maha Visnu, who lies on the Causal Ocean, is an expansion of Sankarsana. When Garbhodakasayi Visnu accepts the material modes of nature for the purpose of dissolving the cosmic manifestation, His form is called Rudra. As already explained, Lord Visnu is the controller of maya. How, then, can He associate with maya? The conclusion is that the incarnation of Lord Siva or Lord Brahma indicates the absence of the supreme power of Visnu. When the supreme power is not there, it is possible to associate with maya, the external energy. Lord Brahma and Lord Siva are to be considered creations of maya.
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