Bhagwan Shiv as the cosmic dancer, symbolises the life force. Through his cosmic dance, he represents the rhythmic divine energy of the universe and realises us from all egos.\ImageSource
Dance and Music are called the Gandharv Vidyas, as they belong to the creative genre. Bhagwan Shiv is the greatest exponent in these arts and they are his favourites. The dance offered as worship is the dearest to him. The energy of life moves in rhythm for him, and hence the vedas are also chanted in rhythm during his worship. However, his incarnation as Nataraj, the God of Dance has a very interesting story.
In the forest of Thillai, (present Chidambaram in Tamil Nadu), there dwelled sages who did not practise their austerities and led a life involved in pleasure and desire. Bhagwan Vishnu and Bhagwan Shiv decided to teach them a lesson. Bhagwan Shiv in guise of a handsome young bramhin and Bhagwan Vishnu is disguise of a beautiful dancer Mohini went to the forest and attracted the sages and their wives. The sages got attracted to Mohini, while their wives to Bhagwan Shiv. Shiv Ji as the handsome Brahmin aroused the passion of the wives and led them into the forest. After sometime, the sages realised that this was all the maaya created by both, and went in search of their wives. They saw the wives being attracted to Bhagwan Shiv and were angry. Out of their arrogance, they decided to punish Bhagwan Shiv.\
They created a sacrificial fire and started performing a yagn from which a huge tiger emerged. Shiv Ji easily killed the tiger and adorned its skin around his waist as his cloth. Then, a trident came to hurt him, but he clutched it firmly in his right hand and it became his weapon. Then an antelope emerged, but Bhagwan Shiv caught hold of it in his left hand. A great snake emerged, which Shiv Ji smilingly garlanded around his neck. A damaru emerged with deafening sound, but Shiva caught it in his hand and played it as a musical instrument. Finally, a demon Apasmara purusha emerged, but Bhagwan Shiv took hold him and pressed him under his right foot. The pressing of the demon under his foot signified the fact that all egos and arrogance get perished under his divine feet.
Then, standing on his right foot, and lifting his left foot in air, he began to dance. This dance became the supreme, energetic dance which had the rhythm of the whole world. All the celestials came to witness the cosmic dance and were filled with joy. It was a heroic victory over the sages who realised their sins and took refuge in Bhagwan Shiv. As the movements of the dance were filled with energy it came to be known as the Tandav (tandu – meaning to jump with energy), and Bhagwan Shiv came to be known as the Nataraj, the Dancing God.
Among the celestials, Sage Patanjali (an incarnation of Seshnag) and sage Vyaghrapad (the sage with the feet of the lion) were totally enthralled by Bhagwan Shiv’s dance wanted to witness the dance once more, and they observed penance in the Thillai forest. Pleased with their devotion, Shiv Ji appeared once more in the form of Nataraj and danced in front of them. This place became famous as Chidambaram and Bhagwan Shiv is worshipped as Nataraj here, in the temple of Chidambaram.