Metta Sutta
Background Story
On one occasion, some five hundred bhikkhus (monks), after obtaining an object of meditation from the Buddha went into the Himalayan forest to practise meditation. Initially, the devas residing in the trees tolerated their presence, but as they learnt that the bhikkhus would not leave so soon, the devas made fearful sights and sounds at night to frighten the bhikkhus so that they would go away. The bhikkhus were so disturbed that they got sick and could not make any progress in their meditation. They decided to leave the place and reported their experiences to the Buddha.
After surveying, the Buddha found no other suitable location for them to practise meditation than that very forest. Therefore the Buddha advised them to return to the forest and taught them the Metta Sutta as an object of meditation, as well as for their protection. Those bhikkhus returned to the forest, chanted the Metta Sutta, and practised Metta meditation. By doing so, the devas then had goodwill towards the bhikkhus and looked after them. At the end of the Rains Retreat (Vassa), all the five hundred bhikkhus attained Arahantship.