Om Mani Peme Hum - Tibetan Short Form (108 Times)

The Tibetan pronunciation of the mantra is: Om Mani Payme Hung.

Rough translations:
Hail to the Jewel in the Lotus.
Hail to Him who is the Jewel in the Lotus.
Om, the Jewel in the Lotus, Hum. [Page 52]
In the Lotus, the world, exists the Jewel which is the Buddha's Doctrine.
*In the profundity of man's mind introspective meditation discovers the reality, deliverance, Nirvâna, Truth.
In the heart of phenomena the occultist discovers the supreme salvation.
-http://www.theosophical.ca/BlavatskyAsOccultistJR.html

Om Mani Padme Hum" is the short mantra of Chenrezig. [Also known as Avalokiteshvara in India, as Kuan-yin in China, and as Kannon in Japan.]

Whenever we are compassionate, or feel altruistic love for anyone, for an animal or any part of the natural world, we experience a taste of our own Chenrezig nature. Buddhists believe that we all share the same innate mind-nature of unconditional compassion and wisdom.
- http://www.medicinebuddha.org/chenrezig.htm

"Om Mani Padme Hum" is said that all the teachings of the Buddha are contained in this mantra.

The six syllables of this mantra close the doorways to rebirth in the lower realms of cyclic existence. The six syllables also contain the essence of the six perfections of generosity, ethical discipline, tolerance or patience, joyous effort, concentration and wise discrimination.

The Benefits of Chanting OM MANI PADME HUM
by Lama Zopa Rinpoche
"It is also mentioned in the tantras that by reciting this mantra you achieve the four qualities of being born in the Amitabha Buddha pure land and other pure lands; at the time of death, seeing Buddha and lights appearing in the sky; the devas making you offerings; and never being reborn in the hell, hungry ghost or animals realms. You will be reborn in the pure land of Buddha or as a happy transmigratory being.

When one who recites ten malas a day.... Such a person becomes meaningful to behold; being seen and touched becomes a means of liberating other sentient beings. This means that even the person's breath touching the bodies of other sentient beings purifies their negative karma. Anybody who drinks the water in which such a person has swum gets purified.

We are unbelievably fortunate to have met the Dharma and to have the opportunity to do recitation and meditation on the Compassion Buddha. It is an easy way of purifying whatever negative karma we have collected, in not only this life but in many previous lives as well.
Because we have met the Buddhadharma, and especially this methodthe practice of Compassion Buddha and recitation of his mantrait is easy to purify negative karma and collect extensive merit and thus to achieve enlightenment. We are unbelievably fortunate.
Therefore, there is nothing more foolish than not taking advantage of this great opportunity. Normally, we get continuously distracted and waste our lives. Not only that, but all the actions done with ego and with the three poisonous minds of anger, attachment and ignorance create negative karma, the cause of suffering. In all existence, there is nothing more foolish than using this perfect human body to create only suffering.
- http://www.medicinebuddha.org/chenrezig.htm


The mantra OM MANI PADME HUNG
-OM represents the body of all Buddhas;
-MANI means 'jewel';
-PADME, means "lotus";
-HUNG represents the mind of all Buddhas;

MANI refers to the jewel that Chenrezig holds in his two central hands and PADME to the lotus he holds in his second left hand. Saying MANI PADME names Chenrezig through his attributes: "the one who holds the jewel and the lotus." "Chenrezig" or "Jewel Lotus" are two names for the same deity.
When we recite this mantra we are in fact continually repeating the name of Chenrezig. In itself this exercise may look strange. ...this mantra is invested by the grace and power of the mind of Chenrezig who himself gathers the grace and compassion of all the Buddhas and bodhisattvas. ... the mantra is endowed with the capacity to purify our mind from the veils that obscure it. The mantra opens the mind to love and compassion and leads it toward awakening. - http://www.amitabhahospice.org/hospice/compassion.php

Chant is by lama gyurme, thanks to spasserbente (Denmark)