Sonam Gyaitsen, “Thousand-Armed Avalokiteshvara”, Gilt Bronze, ca 1430, Jamchen Monastery, Tibet
The Lotus Sutra is generally accepted to be the earliest literature teaching about the doctrines of Avalokiteśvara. These are found in chapter 25. This chapter is devoted to Avalokiteśvara, describing him as a compassionate bodhisattva who hears the cries of sentient beings, and who works tirelessly to help those who call upon his name. A total of 33 different manifestations of Avalokiteśvara are described, including female manifestations, all to suit the minds of various beings.
One prominent Buddhist story tells of Avalokiteśvara vowing never to rest until he had freed all sentient beings from samsara, the wheel of birth and death. Despite strenuous effort, he realizes that still many unhappy beings were yet to be saved. After struggling to comprehend the needs of so many, his head splits into eleven pieces. Amitābha, the Celestial Buddha, seeing his plight, gives him eleven heads with which to hear the cries of the suffering. Upon hearing these cries and comprehending them, Avalokiteśvara attempts to reach out to all those who needed aid, but found that his two arms shattered into pieces. Once more, Amitābha comes to his aid and invests him with a thousand arms with which to aid the suffering multitudes.