Lord Vishnu incarnated Varaha Avatar in Sat- Yug to help mother earth. One day Lord Brahma’s four sons came to meet Lord Vishnu at his abode – Vaikunth. Since Lord Vishnu was resting at that time, the two guards named Jaya and Vijaya stopped them from entering the gates.Lord Brahma’s sons were very angry and they cursed Jaya and Vijaya to be born as humans on earth. Guards pleaded them but Lord Brahma’s son wouldn’t listen.
Lord Vishnu after hearing some noises arrived at the spot and apologized for his guards, saying they were just doing their duty.But the curse can’t be taken back saying this Lord Brahma’s sons left. Lord Vishnu then addressed his guards and said that curse would be lifted if you both in human forms would meet your death at my hands. The guards had no choice but to agree to this. Both the guards were born as brothers named Hiranyakashyap and Hiranyaksha.
Hiranyaksha was a great devotee of Lord Brahma. He worshiped him for years and in return Lord Brahma gave him a boon. According to the boon no God, human, Asura, devta ,animal or beast would kill him. Hiranyaksha started torturing the people on earth as he was assured of his immortality. His powers grew by the day.He was such a giant that mother earth trembled when he walked and the sky cracked when he shouted.
He started harassing devtas and invaded Indra’s palace. Fearing for their life devtas took shelter in the caves of mountain ranges of earth. To harass devtas, Hiranyaksha grabbed earth and submerged it in paatal lok. Mother Earth sank to the bottom of the ocean. At that time Manu and his wife Shatarupa ruled over earth.
Seeing this Manu & his wife came to Lord Brahma, bowed and said, “Father tell us how we may serve you & ensure our happiness in this world & the next.Where should I and Shatarupa live as Mother earth is submerged in the ocean?” Brahma ji became worried and thought that mother earth should be rescued. He said, “Hiranyaksha will not be destroyed by me because I have granted him a boon. Let’s take help of Lord Vishnu!”
As Brahma meditated to Lord Vishnu a tiny Boar* fell from his nostrils. Wondering what that creature was, it grew and grew till it was a size of a large Mountain. It was Lord Vishnu and he said, “I will enter into the ocean to lift Mother earth out of it.”
Emitting a terrifying roar, he (Lord Vishnu in the form of Boar) took one mighty leap into the air and tore the clouds with its hoofs and dived to the bed of ocean in search of Mother earth. He reached the other end of the ocean and discovered in its depths Bhoomidevi ( Mother Earth).
Meanwhile Hiranyaksha rushed to the sea shore where he encountered with Varuna, lord of the ocean, and challenged him,”O supreme Lord! O guardian of the whole sphere! come & have battle with me.” Varuna became very angry as he knew that at this moment Hiranyaksha was mightier than him so he curbed his anger & said, “I have given up fighting as I am too old. You must fight with Vishnu; none but he alone would be an equal opponent for you. Go seek him out.”
Suddenly Narad arrived there. Hiranyaksha asked him, “Do you know the whereabouts of Vishnu?” Narad told him that Lord Vishnu was in the ocean rescuing Mother Earth. Angry Hiranyaksha charged towards the ocean -bed.
Meanwhile the Boar had just dug his tusk into the ocean-bed and lifted Mother Earth onto it, and began rising towards the surface. Hiranyaksha rushed towards him with a mace in his hand saying, “You fraudulent fellow! Where are you carrying away the earth conquered by me? Stop or I’ll crush your head with this mace!”
Hiranyaksha challenged Lord Vishnu in the Boar form to have battle with him but Vishnu ignored all his warnings and continued rising to the surface. Seeing this Hiranyaksha gave a chase, but the boar didn’t even looked back.
Hiranyaksha said, “Wait! You impostor! I know you can defeat all with your magic power but at present you are near me and I’ll surely defeat you.” The boar escaped to put mother earth at a safe place.
Hiranyaksha became very angry and shouted, “How can you run away like a coward? Return me my earth.” The earth was already frightened but seeing Hiranyaksha it began to tremble more.
Lord Vishnu in Varaha avatar brought earth over the surface of ocean and placed it gently on it’s axis and blessed her. He then turned to face Hiranyaksha. The demon threw his mace at the boar but the boar stepped aside and raised his mace. They fought for a long time with their mace.
Now Brahmaji warned Vishnu, “You’ve only an hour before the sunset. Destroy the demon before it’s dark so that he gets no opportunity to resort his black magic.” Hearing Brahma’s word’s Hiranyaksha hurled his mace towards Lord Vishnu but later flung it away. Having lost the mace, Hiranyaksha began hitting out with his fists on the chest of the boar.
Lord Vishnu in Varahaavatar hit Hiranyaksha hard on his face with his fist and tossed him in the air. He fell over his head and died on the spot. Manu got his earth back and the gods their heaven.
In this way Lord Vishnu in Varaha avatar slew Hiranyaksha and saved Mother Earth from harm.
* Why did Lord Vishnu take the boar avatar? Because among all the animals Hiranyaksha forgot to mention boar as an animal, and Lord Vishnu took this form to kill him.