At one time in the past, the God of Compassion - Avalokitesvara, raised the idea of enlightenment, the Bodhicitta, and then, for countless aeons accumulated merit. After passing through the bodhisattva levels, he received the special Great Light empowerment.

Then, as he entered the ranks of the Noble Sons of the Buddha, he made the vow – ‘Throughout the samsaric realms in the limitless space of the ten directions. I will benefit beings. I must liberate all beings from samsara. Not until all beings are established on the level of Buddhahood, with not even one left behind in samsara, will I myself enter Buddhahood. Only when all beings, without exception have been guided to Buddhahood, will it be well for me to achieve it. Until then I will remain in samsara for the benefit of all beings. And to ensure it, may my body be shattered into a thousand pieces if I should ever break this vow.’

From then on, Avalokitesvara resided at the Potala Mountain. Through his limitless emanations he accomplished the ripening and liberating of innumerable sentient beings. And thus, he passed many, many kalpas, engaged in delivering upon his sacred vow.

Finally, he thought that he had delivered all beings from samsara. With his omniscient vision he looked, and saw that the realms of sentient beings had neither increased nor diminished. Not only had they not decreased in number, those sentient beings near him were in the Age of Darkness, and had become even more difficult to subdue. Then saying, ‘Now, I cannot benefit even one sentient being,’ Avalokitesvara broke the vow he had previously made, and therefore his body shattered into a thousand pieces.

At that moment the Buddha Amitabha, appeared and said ‘son of my family, it is not well that you have thus broken your vow. Now you must replenish your broken vow, and make an even greater resolution to benefit beings.’ The shattered body of a thousand pieces, by Amitabha's blessing, was united into one body with eleven heads and a thousand arms. And thus he came to be known as Chukchi Zhey ‘the one with eleven heads,’ and also as Chaktong Chentong ‘ the one with thousand hands and thousand eyes.’ The thousand hands and thousand eyes were intended to make it easier for him to accomplish his task and fulfill his vow.

Avalokitesvara thought that his previous great vow could never be exceeded. And yet, in trying to fulfill it he had been unable to benefit even a few beings. So for seven days he was unable to decide what to do. Finally, he decided that by means of a wrathful form he would be able to subdue the degenerate beings of this Age of Darkness. He felt that through his wrathful form he could be able to assist the many beings who practiced Dharma but were unable to escape from the realms of Bardo (the intermediate realms). Through his new form he wanted to provide an antidote to the sufferings experienced by the beings of the Dark Age, whereby those beings could have their needs fulfilled simply by making a wish.

With this three-fold activity his vow became even greater than before. From the form of Avalokitesvara emerged a dark blue letter ‘Hung,’ which instantaneously transformed him into the Protector of Wisdom. In all the Pure Lands, the very grounds shook with six kinds of earthquakes. The Conquering and Transcending One of Immeasurable Light and all other Tathagatas of the ten directions proclaimed in one voice, ‘Son of the family, it is well that you have made this resolution. You shall have the empowerment of all the wisdom Dakinis. You shall have the strength of the wrathful Yama, Lord of Death. You shall have the mountain spirits - the yaksas, the devils and the demons as your messengers. You shall embody the great wrathful empowerments of the Body, Speech, Mind, Qualities, and activity of all the Buddhas throughout the three times.’ Ever since then, Mahakala – ‘the Black One of Great Compassion,’ as he came to be known, has remained as the Doctrine Protector of all the Buddha fields.

The Protector's body is midnight blue (also black), symbolic of the changeless Dharmakaya.

His three eyes symbolize his knowledge of the past, present and future, and also the manifestation of the three bodies of the Buddha.

The crown adorned with five skulls symbolizes the transformation of the five poisons of anger, desire, ignorance, jealousy and pride into the five wisdoms.

His six arms symbolize the attainment of the six Perfections - generosity, patience, morality, diligence, meditation and wisdom.

The Kartika or Triku - the ritual curved knife, cuts attachment to the ego.

The Kapila or skull bowl filled with blood symbolizes the subjugation of the maras or evil ones.

The Rosary symbolizes his continuous activity for the benefit of all sentient beings.

The Damaru or hand-drum symbolizes his power over the dakinis.

His Trident symbolizes his power over the three kayas -- the spheres of desire, form and formlessness.

The Lasso binds those who break their vows.

His two feet are the means and the wisdom to accomplish his task. That his left leg is straight and his right leg bent symbolizes his accomplishment of the benefit to oneself and to others.

He tramples on a Vinayaka, to symbolize his destruction and dispersal of great obstacles.

The sun on which he stands symbolizes his illumination of the darkness of ignorance.

His Lotus seat symbolizes purity undefiled by samsara.

The surrounding blazing fire symbolizes his activity that consumes neurotic states.

The tiger skin stands for purification of desire; the elephant skin for purification of pride, and the snake, for the purification of anger.

His other ornaments together symbolize that he has all the qualities of a Buddha.

And HE is the Protective Deity of Bhutan.