Garuda was given to the permission to eat snakes by Indra, the king of Devas, after Garuda agreed to return the Amrita Kumbha or elixir. Garuda had stolen the pot from Devas after the samudra manthan or churning of ocean. So, why did Garuda stop eating snakes?
After getting permission to kill and eat snakes, the population of snakes decline drastically as Garuda killed and several of them a day. Finally, a decision was taken as per which a snake will become the food of Garuda daily.
It was the day of Naga Shankhachuda to become the food of Garuda. But when he reached the spot, Vadya Shila (rock). Shankachood saw Jimutavahana, who was the king of vidyadharas (semi divine beings), sitting on the rock.
When young Shankachood narrated the reason for his visit, Jimutavahana took pity on the young serpent and agreed to become food of Garuda.
Garuda soon arrived and thought Jimutavahana to be Shankachood and carried him to Malaya Mountain.
But soon Garuda realized the mistake and listened to Jimutavahana. Garuda was moved by the self sacrifice of Jimutavahana.
Garuda gave the word to Jimutavahana that he will not eat snakes henceforth. Garuda also promised the king of Vidyadharas that he will bring back to life all the snakes that he had killed.