The Vajra has a special significance in Tibetan Buddhism and has a direct connection to the esoteric branch of Mahayana - Vajrayana. The vajra also is a literal ritual object associated with Tibetan Buddhism, also called by its Tibetan name, Dorje.
It is the symbol of the Vajrayana school of Buddhism, which is the esoteric branch that contains rituals said to allow a follower to achieve enlightenment in a single lifetime, in a thunderbolt flash of indestructible clarity.
At the center of the vajra is a small flattened sphere which is said to represent the underlying nature of the universe.
It is sealed by the syllable hum (hung), representing freedom from karma, conceptual thought, and the groundlessness of all dharmas.
Outward from the sphere, there are three rings on each side, which symbolize the three-fold bliss of Buddha nature.
The next symbol found on the vajra is two lotus flowers, representing Samsara (the endless cycle of suffering) and Nirvana (release from Samsara).
The outer prongs emerge from symbols of Makaras, are sea monsters.
The number of prongs and whether they have closed or open tines is variable, with different forms having different symbolic meanings. The most common form is the five-pronged vajra, with four outer prongs and one central prong. These may be considered to represent the five elements, the five poisons, and the five pearls of wisdom. The tip of the central prong is often shaped like a tapering pyramid.
The Crossed Vajra or Vishvavajra
The vishvavajra, as the crossed or ‘universal’ vajra, which underlays the foundation of Mt. Meru’s universe, represents the principle of absolute stability, characterized by the solidity of the element earth.
Bodh Gaya, where Shakyamuni Buddha attained the realization of enlightened ‘vajra-mind’ is also known as Vajrasana or ‘vajra-seat’. The posture in which he sat, and in which the vast majority of seated deities are also depicted, is known as ‘vajra-posture’ with legs crossed in the opposite manner to the Hindu ‘full-lotus’ posture of Padmasana.
The raised wooden throne on which sit high lamas, such as the Dalai Lama, is usually decorated on its front with a hanging silk brocade square which displays the vishvavajra at its center, often with four swastikas in the corners. This emblem represents the indestructible reality of Buddha’s vajra mind as the unshakable throne or ground of enlightenment.
The relationship between the crossed vajra and the swastika, as stability symbols of the element earth, also finds expression in the visualization or drawing of a vishvavajra or swastika under a practitioner’s meditation seat during a retreat.
Similarly, the emblem of a crossed vajra is inscribed on the metal base that is used to seal deity statues after they have been consecrated. If the vertical vajra represents the visualized generation of the deity, the horizontal vishvavajra represents the visualized generation of the deity’s mandala palace, symbolizing the stability of the vajra-earth upon which it rests.
It’s also an emblem of the green buddha of the north, Amoghasiddhi, and represents his all-accomplishing wisdom as lord of the karma family of activity.