Why is Krsna Sometimes Called Visnu?
From Ujjvala Nilamani, an amazing commentary by Viisvanatha Chakravarti Thakura:
“The word Visnu here means Krsna., who is called Visnu because He spreads Himself everywhere. The root vis means to spread. Radha is dear to Krsna who is spread with srngara-rasa, since the word priya is used in this sentence. Just as Radha is dear to Krsna who spreads out and embraces the soul, intelligence, body and senses of Radha – Her kunda is dear to Krsna (Visnu), who spreads Himself out into the water, steps, groves, gardens, flowers, fruits, birds and their cooing, by bathing, sitting, lying down, playing, seeing, smelling, tasting and hearing at that kunda.
But it is said that other gopis are also dear to Krsna.” That is true. Embracing them all by manifesting Himself in unlimited forms (spreading himself – Visnu), He shows intense affection.”
“The king of the groves, equipped with the six elements necessary for the arts of Cupid, rules the excellent kingdom of romantic love. In one place He picks a quarrel with His beloved women. In another place He dispatches love letters along with parrots. In another place He becomes eager to meet for pastimes. In another place He resolves differences using a go-between, and in another place, He unites with a gopi. BRS, 2.1.332