Samudra Manthan happened in Satya Yuga...
The churning of the Ocean of Milk or the Milky Way was an elaborate process. Mount Mandarachala was used as the churning rod, and Vasuki, the king of serpents, became the churning rope. The demons (asuras) demanded to hold the head of the snake, while the demigods (devas), taking advice from Vishnu, agreed to hold its tail. As a result the demons were poisoned by fumes emitted by Vasuki. Despite this, the demigods and demons pulled back and forth on the snake's body alternately, causing the mountain to rotate, which in turn churned the ocean. However, once the mountain was placed on the ocean, it began to sink. Vishnu in his second incarnation, in the form of a turtle Kurma, came to their rescue and supported the mountain on his back.
During the Samudra Manthan by the gods and demons, one of the product emerged from the churning was a dangerous poison (Halahala). This terrified the gods and demons because the poison was so toxic that it might have destroyed all of creation. On the advice of Vishnu, the gods approached Shiva for help and protection. Out of compassion for living beings, Shiva swallowed the poison in an act of self-sacrifice. However, his consort Parvati who was looking on, terrified at the thought of his impending death, prevented the poison from descending into his body. Thus the poison was stuck in Shiva's throat with nowhere to go, and it was so potent that it changed the color of Shiva's neck to blue. For this reason, he is also called Nilakantha (the blue-throated one; "neela" = "blue", "kantha" = "throat" in Sanskrit). When the heat from the poison had become unbearable Shiva is supposed to have used his trishul to dig for water forming the Gosaikunda lake which is in Nepal.
This story is supported by Bhagvat Puran,Vishnu Puran,Mahabharat...
The Avatars of Vishnu
The ten Avatars are:
1. Matsya (the fish) . Fish that rescues Veda, plants and animals. One of the ten avatars of Vishnu that appeared in the Satya Yuga.
2. Koorma (the tortoise).Tortoise that supports the churn of the ocean to obtain treasures dissolved in the ocean of milk. One of the ten avatars of Vishnu that appeared in the Satya Yuga.
3. Varaha (the boar). Boar that raise the earth from the bottom of the sea. One of the ten avatars of Vishnu that appeared in the Satya Yuga
4. Narasimha (the human-lion) .Man-lion who defies classification and overpowers mortals(Hiranyakashipu) who seek to outwit death. One of the ten avatars of Vishnu that appeared in the Satya Yuga.
5. Vamana (the dwarf) .Dwarf who claims from King Bali) the sky from the gods and buries the demons in the underbelly of the earth. One of the ten avatars of Vishnu that appeared in the Treta Yuga
6. Parasurama (the angry man, Rama with an axe). Priest who turns to violence to kill unrighteous kings and unchaste women. One of the ten avatars of Vishnu that appeared in the Treta Yuga.
7. Lord Rama (the perfect man, king of Ayodha) .King who uploads old rules at the cost of personal life. One of the ten avatars of Vishnu that appeared in the Treta Yuga
8. Lord Krishna (the divine statesman) .Cowherd/charioteer/stateman who shrewdly changes rules. One of the ten avatars of Vishnu that appeared in the Dwapara Yuga
9. Lord Buddha
10. Kalki (the mighty worrior)
The last Avatar is yet to appear.
Edited by flamingo_aries - 13 years ago