In Hindu mythology, Durvasa was an ancient and chief of sages. Known for His temperamental nature, Durvasa was the son of Atri by Anasuya and was an incarnation of a portion of Shiva “The Destroyer”.
According to Vishnu Purana (one of the eighteen traditional puranas), Durvasa was wandering on Earth in a state of pure altered consciousness, with highly raised spiritual awareness due to a divine vow of insanity, came by Vidyadhari , (a female spirit who possesses middle regions of the atmosphere) and demanded for garland she was wearing, (according to the Vayu, the garland was given to Vidyadhari by Devi). Knowing the nature of Durvasa, Vidyadhari bowing to him reverentially, presented garland to the sage.
Durvasa wore it on his forehead and resumed wandering around.
While further wandering, Durvasa came across Indra (the Ruler of the 3 worlds) riding his elephant Airavata. Durvasa, still in a frenzy state of mind, took off garland from his forehead and threw it at Indra. Indra caught garland right in and hanged it over his elephant Airavata’s brow. Attracted by the fragrance of garland, Airavata took hold of the garland and cast it down on land. Watching this gesture of Indra, Durvasa was highly incensed at this disrespectful treatment of his gift and cursed Indra that he would be cast down from his position as a ruler of the three worlds, just as the garland was treated by him. Indra begged for forgiveness but Duravasa refusing, said: “What need of words? I will not forgive whatever aspect of humility you can assume.” and went his way.
Curst from Durvasa, Indra and Devas lost their strength. All vegetables, plants and herbs were diminishing to death in the three worlds ruled by Indra and were stripped off with prosperity. Seizing the opportunity and weakness of Devas, the Danavas (enemies of Devas), put forth their war of strength against Devas. The ambitiously agitated Danavas engaged in war with the unfortunate divinities, somehow Indra and survived Devas fled for refuge with Brahma “The Creator”.
The Creator of World, Brahma directed them to seek refuge with Vishnu “The Preserver of the Universe”. Vishnu, advised Devas to call a peace with Danavas and associatively churn the sea of milk together for equal portion of fruit. Also promising Danavas, the Amrit that shall be produced from the agitated ocean, with which they would become mighty and immortal. Vishnu directed to take mountain Mandara for churning as a stick in the ocean, the serpent Vasuki as a rope, positioning Devas at the tail and Danavas at the head of the serpent Vasuki. Vishnu promised, that he would ensure only Devas drank the Amrit and achieve immortality and defeat Danavas.
Churning the ocean for 1000 years, eventually Dhanwantari the divine robed in white, appeared with “Kumbh” containing the Amrit. The Danavas ran away snatching Kumbh from Dhanwantari, chased by the Devas. For 12 days and 12 nights (equalling to 12 human years), the Devas and Danavas fought in the sky for the possession of this pot of Amrit “Kumbh”. It is said that during the battle, drops of Amrit were fallen on four places of the Earth: Prayag, Haridwar, Ujjain and Nasik.
Source: Krishna Vashistha