Mahabali was a great Asura king who had defeated Devas in war. He had become King of all the three worlds – Prithvilok (Earth), Devlok (Heaven) and Paatallok (Netherworld). He was a just, able and a very generous king. People were very happy during his rule. He was a great devotee of Vishnu. He was the grandson of the great Vishnu bhakt, Prahlad and a descendent of Rishi Kashyap. Mahabali had temporarily possessed Amrit which was an outcome of ‘Samudra manthan’. When he died in one of the battles between Devas and Asuras, he was given the ‘Amrit’ and was brought back to life. Thus, Mahabali had become immortal.
Mahabali’s growing popularity made the Devas very insecure. They went to Vishnu to seek help. The Devas said, ‘O great Lord! Please free us from the rising power of Raja Mahabali!!’ Vishnu replied, ‘I will not do such a thing. Bali is a great devotee of mine and I don’t see a reason to kill him.’ Hearing this the Devas pleaded, ‘O Lord Vishnu! He has become all powerful and a threat to us. Please help us.’ Lord Vishnu thought for a while and said ‘I will do what is appropriate.’ and then he closed his eyes and went into a slumber.
One day Raja Bali was performing a yadna at a river bank. Lord Vishnu took the avatar of ‘Vaman’ a dwarf Brahmin and arrived at the place where the ‘yadna’ was happening. Raja Bali welcomed the Brahmin with great respect and hospitality. The Brahmin asked the King for alms. King Mahabali said, ‘Ask anything you wish!’. Vaman replied, ‘I seek land that is covered by my three steps.’
On hearing Vaman’s wish, Shukracharya, the Guru of the Asuras tried to persuade Bali to not grant him his request. Shukracharya had realised that the young boy was Lord Vishnu himself. Raja Bali did not listen to his Guru and he promised to give Vaman the land which would cover his three steps.
Vamana suddenly expanded and grew into a gigantic size. He placed one step on Prithvilok (Earth) and the second step on Devlok (Heaven). Now there was no place to keep the third step. Seeing this Mahabali said, ‘O great Brahmin! please keep your third step on my head.
The moment Lord Vishnu in his ‘Vaman’ avtar stepped on Bali’s head, Bali was pushed into Pataallok (Netherworld). Lord Vishnu was immensely pleased with the benevolance of his great devotee, Mahabali. Vishnu appeard in his true form and said, ‘I bless you Bali. From now on you will rule Paatallok (Netherworld) forever.’ He also granted Bali a boon and said ‘Every year you can visit Prithvilok for a day to meet your people and subjects.’ Mahabali bowed with folded hands to Lord Vishnu and thanked him for his blessings and boon.
The auspicious day when Mahabali visits Prithvilok every year to meet his subjects and people is celebrated as ‘Onam’ in Bharat and specially in Kerala (the land of Mahabali). Onam is celebrated on Chaturdashi Tithi of Shukla Paksha in the Holy month of Shravan.
