svarupa--aisvarya-purna, krsna-sama praya
krsna amsi, tenho amsa, vede hena gaya
sva-rupa—personal expansion; aisvarya-purna—full of all opulences; krsna-sama—equal to Krsna; praya—almost; krsna amsi—Krsna is the Supreme Personality of Godhead; tenho—Lord Visnu; amsa—personal expansion; vede—the Vedas; hena—thus; gaya—sing.
"Lord Visnu is in the category of svamsa because He has opulences almost equal to Krsna's. Krsna is the original person, and Lord Visnu is His personal expansion. This is the verdict of all Vedic literature.
Although an incarnation of the material energy, Lord Brahma is nonetheless the director of the material mode of passion. Similarly, Lord Siva, although simultaneously one with and different from Lord Krsna, is still the incarnation of the mode of darkness. However, Lord Visnu is Krsna's personal expansion; therefore He is the director of the mode of goodness and is always transcendentally situated beyond the jurisdiction of the modes of material nature. Lord Visnu is the original personal expansion of Krsna, and Krsna is the original source of all incarnations. As far as power is concerned, Lord Visnu is as powerful as Lord Krsna because He possesses all the opulences.
Link to this page: http://prabhupadabooks.com/cc/madhya/20/315