Akshobhya appears in the "Scripture of the Buddha-land of Akshobhya" (阿閦佛國経 Ä�chùfó guó jÄ«ng), which dates from 147 AD and is the oldest known Pure Land text. According to the scripture, a monk wished to practice the Dharma in the eastern world of delight and made a vow to think no anger or malice towards any being until enlightenment. He duly proved "immovable" and when he succeeded, he became the buddha Akshobhya.
Akshobhya is sometimes merged with Acala (Japanese: �動明王 Fud� my�-�), whose name also means 'immovable one' in Sanskrit. However, Acala is not a buddha, but one of the Five Wisdom Kings of the Womb Realm in Vajrayana.
Akshobhya is the embodiment of 'mirror knowledge' (Sanskrit: Ä€darÅ›a-jñÄ�na; refer Panchajnana). A knowledge of what is real, and what is illusion, or a mere reflection of actual reality. The mirror is mind itself - clear like the sky, empty yet luminous. Holding all the images of space and time, yet untouched by them. He represents the eternal mind, and the Vajra family is connected with reason and intellect. Its brilliance illuminates the darkness of ignorance, its sharpness cuts through confusion.
The Vajra family, to which Akshobhya belongs, is associated with the element of water. This is why the two colors of Vajra are blue or white. Bright white like sun reflecting off water, and blue, like the depths of the ocean. Even if the surface of the ocean is blown into crashing waves, the depths remain undisturbed, imperturbable. And though water may seem ethereal and weightless, in truth it is extremely heavy. Water flows into the lowest place and settles there. It carves through solid rock, but calmly, without violence. When frozen, it is hard, sharp, and clear like the intellect, but to reach its full potential, it must also be fluid and adaptable like a flowing river. These are all the essential qualities of Akshobhya.
Many wrathful tantric beings are represented as blue in color because they embody the transmuted energy of hatred and aggression, into wisdom and enlightenment
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Splendidly, the colour of the sky in daylight is blue in colour, and the ocean is blue in colour around deep sea regions. Simply, all deep and sweet is blue in colour, the symbolic of the truth in living beings' loving-kindness and pleasantness. Amazingly, the blue colour is applied in true science of beings' nature in Buddhism literature.
Namo Amitabah!