Vajrasattva is pure white in colour and is sometimes known as the Prince of Purity. His name means "Adamantine Being", or more poetically "Embodying Reality". He is a member of the Vajra family of Akṣobhya which also includes Vajrapāṇi.
He is depicted as a young man in the prime of life, with all the silks and jewels of a wealthy prince. In his right hand he delicately balances a vajra at his heart. In his left had he holds a bell at his waist. The vajra represents Reality, and Compassion; while the bell represents Wisdom.
In some mandalas Vajrasattva represents the Ādibuddha or the Primordial Principle of Buddhahood; in others he changes places with Akṣobhya in the East. In Shingon Buddhism it is Vajrasattva that passes on the initiation of the Dharmakāya Buddha Mahāvairocana to Nāgārjuna, thereby creating the Vajrayāna lineage.
In the mūla-yogas the practitioner carries out a set of four pactices 100,000 times. One of these is visualising of Vajrasattva and repeating his 100 syllable mantra 100,000 times which helps to purify the karma of the person intending to go on to the tantra proper. Completing these practices is seen as essential prior to receiving initiations or ordination in some Tibetan lineages.
The seed syllable hūṃ is shared by a number of Buddhas and Bodhisattvas, especially those associated with the Vajra family of which Vajrasattva is the epitome. Other members are Vajrapāṇi, and Akṣobhya
|hūṃ Siddham||hūṃ Tibetan - Uchen|
Vajrasattva is associated with the hundred syllable mantra, the chanting of which is used in rituals of purification especially funerals (see below). There is also a short version of the Vajrasattva mantra. We'll start with the short mantra.
The short Vajrasattva mantra
oṃ va jra sa ttva hūṃ
oṃ vajrasattva hūṃ
The 100 syllable Vajrasattva mantra
oṃ va jra sa ttva sa ma yam a nu
pā la ya va jra sa ttva tve no pa
ti ṣṭha dṛ ḍho me bha va su to ṣyo
me bha va su po ṣyo me bha va a
nu ra kto me bha va sa rva si ddhiṃ
me pra ya ccha sa rva ka rma su ca
me ci ttaṃ śre yaḥ ku ru hūṃ ha ha
ha ha hoḥ bha ga van sa rva ta thā
ga ta va jra mā me mu ñca va jrī
bha va ma hā sa ma ya sa ttva aḥ
vajrasattva samayam anupālaya
dṛḍho me bhava
sutoṣyo me bhava
supoṣyo me bhava
anurakto me bhava
sarva siddhiṃ me prayaccha
sarvakarmasu ca me cittaṃ śreyaḥ kuru
ha ha ha ha hoḥ
bhagavan sarvatathāgatavajra mā me muñca
vajrī bhava mahāsamayasattva
Tibetan - Uchen
Below is the Vajrasattva mantra in Tibetan Unicode - you might need a special font to see this.
ཨོཾ་བཛྲ་སཏྭ་ས་མ་ཡ་མ་ནུ་པ་ལ་ཡ། བཛྲ་སཏྭ་ཏྭེ་ནོ་པ་ཏིཥྛ། དྲྀ་ཌྷོ་མེ་བྷ་བ། སུ་ཏོ་ ཥྱོ་མེ་བྷ་བ། སུ་པོ་ ཥྱོ་མེ་བྷ་བ། ཨ་ནུ་ར་ཀྟོ་མེ་བྷ་བ། ས་རྦ་སི་དྡྷི་མེ་པྲ་ཡ་ཙྪ། ས་རྦ་ཀ་རྨ་སུ་ཙ་མེ ཙི་ཏྟཾ༌ཤེ་ཡཿ་ཀུ་རུ་ཧཱུྂ། ཧ་ཧ་ཧ་ཧ་ཧོཿ བྷ་ག་བ་ན ས་རྦ ཏ་ཐཱ་ག་ཏ་བཛྲ་མཱ་མེ་མུ་ཉྩ། བཛྲཱི་བྷ་བ་མ་ཧཱ་ས་མ་ཡ་སཏྭ ཨཱཿ །། ཧཱུྂ ཕ་ཊ
O Vajrasattva honour the agreement!
Reveal yourself as the vajra-being!
Be steadfast for me!
Be very pleased for me!
Be fully nourishing for me!
Be passionate for me!
Grant me all success and attainment!
And in all actions make my mind more lucid!
ha ha ha ha hoḥ
O Blessed One, vajra of all those in that state, don't abandon me!
O being of the great contract be a vajra-bearer!
The Sanskrit version of the 100 Syllable mantra follows the edited text of the Sanskrit and produced by Dharmacari Sthiramati (aka Dr. Andrew skilton) in his article: The Vajrasattva Mantra : notes on a corrected Sanskrit text. (Order Journal [of the Western Buddhist Order] vol.3 Nov. 1990). Note this is different from the version in the 1st ed. of the FWBO Puja book and this edited version was produced to fix problems with that version. The English translation is my own - see also my notes on translating the mantra.
The basic mantra ends with āḥ. Hūṃ and phaṭ are traditionally added under specific circumstances - hūṃ when the mantra is recited for the benefit of someone dead, and the phaṭ when the mantra is recited to subdue demons. They are not present in the Tibetan example above, however in the WBO/FWBO they are routinely included.
I've adopted a practice which seems standard in Japanese calligraphy, but about which I am not certain, which is to write words like muñca as muṃ ca, instead of mu ñca, using the anusvāra to replace the nasal. This would appear to be related to the principle of economy of effort in Sanskrit literarture which reduces any writing to the minumum of words, characters and letters - and in this case pen strokes. It would still be possible to only use 100 syllables without using the anusvāra in this way, but would be less lovely.
The Tibetan pronunciation and orthography have diverged somewhat from the Sanskrit and this is my best effort to reproduce it after consulting various sources. There are variations in how it is presented in different traditions. Apologies if this one is not the one that you are familiar with.