The Yamuna River is worshipable, for her greatest pleasure is to serve Krsna and His pastimes in Vraja. One of these pastimes in which the bank of the Yamuna served as a backdrop was Krsna’s killing of Vatsasura, which is described in Bhagavatam Canto 10, Chapter 11, Verses
41-45. Krsna had just begun caring for the calves in the nearbye Vrajabhumi forests.
Srila Jiva Gosvami describes Kamsa’s mood as he sent Vatsasura to his death, which came in the form of his attempt to kill Krsna:
Kamsa was thinking: “Simply hearing Krsna’s name causes my heart to tremble. By some trick, by some clever plan, He must be killed. Already I have tried plan after plan, each one more clever than the last, but all have failed. They were useless.”
As he thought in this way, Kamsa walked out of the palace with one of his spies and asked him, “According to what you have seen, whom does Krsna love the most?” The spy reported, “Lord, I think Krsna is most filled with love for His calves.”
Kamsa then ordered, “Now return to your home.” Kamsa then turned to another attendant: “Summon Vatsasura. With his great power he places even the demigod Indra in distress. He makes Indra appear as insignificant as a drop of water.”
Because many others were surrounding him, Kamsa had whispered these words of praise. Vatsasura soon arrived, and Kamsa greeted him as if a son, “Dear child Vatsasura, please go to Nanda’s village of Vraja. Approach Nanda’s small son as He herds the calves. Then, yourself assuming the form of a calf, attack Nanda’s son. Affirming his obedience by saying, “As the king commands, so I will act,” Vatsasura went to the Yamuna’s banks.
The Bhagavatam describes:
“One day while Rama and Krsna, along with Their playmates, were tending the calves on the bank of the River Yamuna, another demon arrived there, desiring to kill Them.”
Sri Jiva adds: “When, as He herded the calves, Vraja’s prince Krsna saw him, Krsna thought Vatsasura was like a poisonous snake.”
The Bhagavatam continues:
“When the Supreme Personality of Godhead saw that the demon had assumed the form of a calf and entered among the groups of other calves, He pointed out to Baladeva, “Here is another demon.” Then He very slowly approached the demon, as if He did not understand the demon’s intentions.”
Jiva Gosvami describes more of this exchange as follows:
“Observing Vatsasura accompany the calves as the sniffed the sweet aromas as they wandered among the grass, Vraja’s prince Krsna said to His elder brother Balarama, “Big brother, which calf is that? I don’t know that calf. That calf was not with Us in the morning.” Balarama replied, “Indeed, brother, that calf was not here then. It was not here.”
Krsna then said, “Tell Me about that calf.”
Balarama said, “I think that calf is dangerous.”
Krsna said, “Older brother, is that calf a demon?”
Balarama said, “Yes. He must be. He stares at Us with hatred-filled eyes.”
Krsna said. “If You command, I will kill this demon.”
Balarama said, “I fear people will criticize You, saying You have killed a calf and have therebye committed a sin.”
Krsna said, “If at the moment of his death this creature manifests his true, original form as a demon, then no one will criticize Me.”
Balarama joyfully said, “O crusher of hated-filled demons, slowly, slowly approach this treacherous demon.”
The Bhagavatam continues:
“Thereafter, Sri Krsna caught the demon by the hind legs and tail, twirled the demon’s whole body very strongly until the demon was dead, and threw him into the top of a kapittha tree, which then fell down, along with the body of the demon, who had assumed a great form.
“Upon seeing the dead body of the demon, all the cowherd boys exclaimed, “Well done, Krsna! Very good, very good! Thank You.” In the upper planetary system, all the demigods were pleased, and therefore they showered flowers on the Supreme Personality of Godhead.
“After the killing of the demon, Krsna and Balarama finished Their breakfast in the morning, and while continuing to take care of the calves, They wandered here and there. Krsna and Balarama, the Supreme Personalities of Godhead, who maintain the entire creation, now took charge of the calves as if cowherd boys.”