"One day Krsna wanted to enjoy a picnic lunch within the forest, and therefore He went out early into the forest with the other cowherd boys, accompanied by their respective groups of calves. While they were enjoying their picnic, Aghasura, the younger brother of Putana and Bakasura, appeared there, desiring to kill Krsna and His companions. The demon, who had been sent by Kamsa, assumed the form of a python, expanding himself to a length of eight miles and the height of a mountain, his mouth seeming to extend from the surface of the earth to the heavenly planets. Having assumed this feature, Aghasura lay on the road. Krsna's friends, the cowherd boys, thought that the demon's form was one of the beautiful spots of Vrndavana. Thus they wanted to enter within the mouth of this gigantic python. The gigantic figure of the python became a subject for their sporting pleasure, and they began to laugh, confident that even if this figure were dangerous, Krsna was there to protect them. In this way, they proceeded toward the mouth of the gigantic figure.
Krsna knew everything about Aghasura, and therefore He wanted to forbid His friends to enter the demon's mouth, but in the meantime all the cowherd boys, along with their groups of calves, entered the mouth of that gigantic figure. Krsna was waiting outside, and Aghasura was waiting for Krsna, thinking that as soon as Krsna entered he would close his mouth so that everyone would die. While waiting for Krsna, he refrained from swallowing the boys. In the meantime, Krsna was thinking of how to save the boys and kill Aghasura. Thus He entered the mouth of the gigantic asura, and when He was within the demon's mouth along with His friends, He expanded His body to such an extent that the asura suffocated and died. After this, Krsna, by casting His nectarean glance upon His friends, brought them back to life, and with pleasure they all came out unhurt. Thus Krsna encouraged all the demigods, and they expressed their pleasure and happiness. For a crooked, sinful person there is no scope for sayujya-mukti, or becoming one with the effulgence of Krsna, but because the Supreme Personality of Godhead entered the body of Aghasura, by His touch this demon got the opportunity to merge into the existence of the Brahman effulgence and thus attain sayujya-mukti."
Srimad-Bhagavatam 10:12 Summary
When Lord Krsna was enjoying His childhood pastimes with His boyfriends, one Aghasura demon became very impatient. He was unable to tolerate seeing Krsna playing, so he appeared before the boys intending to kill them all. This Aghasura was so dangerous that even the denizens of heaven were afraid of him. Although the denizens of heaven drank nectar daily to prolong their lives, they were afraid of this Aghasura and were wondering, "When will the demon be killed?" The denizens used to drink nectar to become immortal, but actually they were not confident of their immortality. On the other hand, the boys who were playing with Krsna had no fear of the demons. They were free of fear. Any material arrangement for protecting oneself from death is always unsure, but if one is in Krsna consciousness, then immortality is confidently assured.
The demon Aghasura appeared before Krsna and His friends. Aghasura happened to be the younger brother of Putana and Bakasura, and he thought, "Krsna has killed my brother and sister. Now I shall kill Him along with all His friends and calves." Aghasura was instigated by Kamsa, so he had come with determination. Aghasura also began to think that when he would offer grains and water in memory of his brother and sister and kill Krsna and all the cowherd boys, then automatically all the inhabitants of Vrndavana would die. Generally, for the householders, the children are the life and breath force. When all the children die, then naturally the parents also die on account of strong affection for them.
Aghasura, thus deciding to kill all the inhabitants of Vrndavana, expanded himself by the yogic siddhi called mahima. The demons are generally expert in achieving almost all kinds of mystic powers. In the yoga system, by the perfection called mahima-siddhi, one can expand himself as he desires. The demon Aghasura expanded himself up to eight miles and assumed the shape of a very fat serpent. Having attained this wonderful body, he stretched his mouth open just like a mountain cave. Desiring to swallow all the boys at once, including Krsna and Balarama, he sat on the path.
The demon in the shape of a big fat serpent expanded his lips from land to sky; his lower lip was touching the ground and his upper lip was touching the clouds. His jaw appeared like a big mountain cave, without limitation, and his teeth appeared just like mountain summits. His tongue appeared to be a broad traffic way, and he was breathing just like a hurricane. The fire of his eyes was blazing. At first the boys thought that the demon was a statue, but after examining it they saw that it was a more like a big serpent lying down on the road and widening his mouth. The boys began to talk among themselves: "This figure appears to be a great animal, and he is sitting in such a posture just to swallow us all. Just see--is it not a big snake that has widened his mouth to eat all of us?"
One of them said, "Yes, what you say is true. This animal's upper lip appears to be just like the sunshine, and its lower lip is just like the reflection of red sunshine on the ground. Dear friends, just look to the right and left-hand side of the mouth of the animal. Its mouth appears to be like a big mountain cave, and its height cannot be estimated. The chin is also raised just like a mountain summit. That long highway appears to be its tongue, and inside the mouth it is as dark as in a mountain cave. The hot wind that is blowing like a hurricane is his breathing, and the fishy bad smell coming out from his mouth is the smell of his intestines."
Then they further consulted among themselves: "If we all at one time entered into the mouth of this great serpent, how could it possibly swallow all of us? And even if it were to swallow all of us at once, it could not swallow Krsna. Krsna will immediately kill him, as He did Bakasura." Talking in this way, all the boys looked at the beautiful lotuslike face of Krsna, and they began to clap and smile. And so they marched forward and entered the mouth of the gigantic serpent.
Meanwhile, Krsna, who is the Supersoul within everyone's heart, could understand that the big statuesque figure was a demon. While He was planning how to stop the destruction of His intimate friends, all the boys along with their cows and calves entered the mouth of the serpent. But Krsna did not enter. The demon was awaiting Krsna's entrance, and he was thinking, "Everyone has entered except Krsna, who has killed my brothers and sisters."
Krsna is the assurance of safety to everyone. But when He saw that His friends were already out of His hands and were lying within the belly of a great serpent, He became, momentarily, aggrieved. He was also struck with wonder at how the external energy works so wonderfully. He then began to consider how the demon should be killed and how He could save the boys and calves. Although there was no factual concern on Krsna's part, He was thinking like that. Finally, after some deliberation, He also entered the mouth of the demon. When Krsna entered, all the demigods, who had gathered to see the fun and who were hiding within the clouds, began to express their feelings with the words, "Alas! Alas!" At the same time, all the friends of Aghasura, especially Kamsa, who were all accustomed to eating flesh and blood, began to express their jubilation, understanding that Krsna had also entered the mouth of the demon.
While the demon was trying to smash Krsna and His companions, Krsna heard the demigods crying, "Alas, Alas," and He immediately began to expand Himself within the throat of the demon. Although he had a gigantic body, the demon choked by the expanding of Krsna. His big eyes moved violently, and he quickly suffocated. His life air could not come out from any source, and ultimately it burst out of a hole in the upper part of his skull. Thus his life air passed off. After the demon dropped dead, Krsna, with His transcendental glance alone, brought all the boys and calves back to consciousness and came with them out of the mouth of the demon. While Krsna was within the mouth of Aghasura, the demon's spirit soul came out like a dazzling light, illuminating all directions, and waited in the sky. As soon as Krsna with His calves and friends came out of the mouth of the demon, that glittering effulgent light immediately merged into the body of Krsna within the vision of all the demigods.
Krsna Book, Chapter 12
Bhaktivedanta Book Trust. Excerpted from text and purport of HDG A.C. Bhaktivedanta Swami Srila Prabhupada.