How did the Shiv Linga actually evolve?
Apart from being a devotee of Lord Shiva, every-one must be having a Shiv Linga at home. Shiv Linga signifies Lord Shiva, thereby it is a strong belief in the minds of the people that by worshipping it with devotion, Lord Shiva would bless the devotee with health, wealth and success.
As per Indian Shastras, Shiv Linga is defined as a cosmic pillar of fire which is the cause of all the happenings or causes. Out of the word Lingam the “Ling” means involution and “Gam” represents evolution, therefore together Lingam is the principle of Evolution and Involution. Also as per Linga Purana, it is a symbolic representation of the formless bearer of the universe. The stone which is in the oval shape looks like the mark of the Universe and its bottom base is represented as the supreme power which holds the entire universe.
However the origin of a Shiv Linga is yet unknown, there is no specific proof or incident which can guarantee about its origin. Apart from this the most widely accepted story comes from the famous hymn in the Atharva-Veda Samhita which is sung in to appreciate and praise the Yupa Stambha.
A description found in that hymn about the beginning less and endless Stambha. It stated that the Stambha represented the never ending and vast Universe and hence the ultimate almighty i.e. Lord Shiva.
Later on the attire of Lord Shiva which is the brightness of Lord Shiva’s body, his tawny matted-hair, his blue throat, and the riding on the bull, and so on were taken from the Yajna fire, its smoke, ashes, and flames, the Soma plant, and the ox that used to carry on its back the wood for the Vedic sacrifice. This is how the Yupa Stambha gave rise to the concept of Shiva-Linga.