Vajra dhatu ah va ra ha kham

Mahā Virocana Tathagata Oṃ Vairocana hūm

Gharbhakosa dhatu ah vi ra hum kham

Mahāvairochana (virocana) is the central figure in Tantric Buddhism, the lord of the Tathāgata family. He represents, in anthropomorphic form, the fundamental principle and the eternal existance of the universe. He is viewed as the embodiment of the 'Awareness of the Continuum of Reality', one of the five awarenesses. His body is said to consist of all forms in the universe, his voice to be all sounds, and his mind to consist of all thought.
He is one of the five Jinas (victor), normally depicted icongraphically as a white saṃbhoga-kāya (Enjoyment body) buddha assiciated with the center or sometimes the eastern quarter. He is known as the great illuminator, the great sun. His mudra is the Dharma chakra (wheel), that of teaching, also known as the turning of the wheel. The index finger and thumb of each hand to make a circle. His symbol is the golden wheel, suggesting benevolent kingship. The element of this tathāgata is water, and he is associated with the crown chakra.

He belongs to the Vajra family. The Vajra, or diamond scepter (thunderbolt) is a powerful emblem of sovereignty -it has the indestructible qualities of the diamond, able to overcome anything that crosses its path. Vairochana helps in overcoming the affliction of ignorance which is the root of samsara (reincarnation). Things come and go; and events keep changing all the time, depending on their behaviors. People is to look for enlightenment, whereby they can stay in eternality and end reincarnation.

There are two forms of the Vidya most commonly associated with Mahavairocana - a va ra ha kham and a vi ra hum kham. In the center is the seed syllable elaborate 'ahm', the very top is plain 'ah'. The Vajra dhatu (diamond realm) represents the wisdom or consciousness aspect of Virocana. In the Gharbhakosa (lit. womb store) dhatu, the Vidya has a complex range of associations but are strongly connected with the 5 elements(dhatu) of earth(prithvi), Water(apas), Fire(agni), Air(vayu), and Space(akasha). Mahavairocana himself represents the 6th element that completes the set of elements which make up all of the universe: ie consciousness. Individual person, animal, plant or matters are all like cells which make up part of the universe, thus the whole universe is the Tathāgata's Gharbha (womb).

Mantra of light  (Amogha Empowerment Light Mantra 不空大灌頂光真言)

   "Oṃ! Amogha vairocana, mahā-mudrā, maṇi-padma, jvala pravartaya hūṃ!" 

     (Om!   a'mo'gha   vi'ro'ca'na   ma'ha-mu'dra   ma'ni-pad'ma   ju'va'la   pra'var'ta'ya   hum!)
Om! invincible Vairocana, the Great (hand) Seal, the Gem (on the) Lotus, the Flame, (Please) come forth, hum!"
  (center- 'Ah' in Siddham Sanskrit)
Vajra dhatu:  Oṃ vajra-dhātu vaṃ
Gharbhakosa dhatu:  Namaḥ samanta- buddhānāṃ a vi ra hūṃ khaṃ   (Adoration to universal buddhas)

Dharmacakra Mudra Dharma(Buddha's Teaching)-Chakra(Wheel) hand Gesture

Om Ah Hum (in Tibetan)

GlossaryOm, AUM (Sanskrit): means oneness with the Supreme, the merging of the physical being with the spiritual. The most sacred syllable, the first sound of Almighty. This scared syllable appears as a mystic sound, regarded as the basis of every other mantra. It is the sound not only of origination but also for dissolution. The past, present and future are included in this one sound and even all that transcends this configuration of time is also implied in OM.
(Ah): A seed syllable of Vajra speech, seed syllable of Virocana
a'mo'gha (不空): invincible, unfailing, infallible, spotless.
Vi'ro'ca'na: lit. means 'universal light'. 'Illuminator', name of Great Sun Buddha.
maha mu'dra: 'maha', great; 'mudra', seal, hand gesture in ritual. One who has the authority (seal).
mani-padma: wish-fulfilling gem, lotus.
pra'var'ta: come forth, begin, proceed. '-ya', passive voice.
jvala (ju va la): flame.
Tathagata: the 'Perfect One' or 'exalted one'. Literally, the one who has 'thus gone', or 'thus come'. It is an epithet for a Buddha.
Vidya: mantra consists of syllables or alphabets, not words.
Hum: Holy mind, destroy all negative distractions!