Long ago, his profound compassion for all beings compelled him to make the following vow: "May I be able to establish in emancipation all the living beings in the barbaric Land of Snow [Tibet], where beings are so hard to discipline and none of the Buddhas of the three times has stepped ... May I be able to mature and emancipate them, each according to his own way. May that gloomy barbaric country become bright, like an island of precious jewels".
He repeated this vow in front of Amitabha, his spiritual father. He vowed: "Until I relieve all living beings, may I never, even for a moment, feel like giving up the purpose of others for my own peace and happiness. If I should ever think about my own happiness, may my head be cracked into ten pieces ... and may my body be split into a thousand pieces, like the petals of a lotus."
Avalokiteshvara then entered a profound state of meditation, directing his compassionate intention to every sentient being, wishing that all of them would be free of their suffering. After a very long time he emerged from his meditation, and was deeply disappointed to see that the vast majority of beings remained trapped within their delusions. His meditation and prayers had helped very few beings out of their misery.
In desperation, he cried out; "What is the use? I can do nothing for them. It is better for me to be happy and peaceful myself." At that moment, by the power of his previous vow, his head split into 10 pieces and his body into one thousand, filling him with unbearable pain. He cried out to Amitabha who immediately appeared before him. Amitabha told him:
All circumstances come from cooperative causes
Conditioned at the moment of intent.
Every fortune which arises to anyone
Results from his own former wish.
Your powerful expression of supplication
Was praised by all the Buddhas;
In a moment of time
The truth will certainly appear.
Amitabha then restored Avalokiteshvara's body, transforming his torn flesh into 1000 hands, each with it's own wisdom eye. He transformed the shattered head into 10 faces, 9 peaceful and one wrathful, so that he could look in all directions and reach out compassionately and forcefully to all beings. To show how pleased he was with Avalokiteshvara, he crowned the 10 faces with a replica of his own.http://www.kalsangdawa.com/gallery/1000arm.htm