This kind of Shiva's anthromorphic image serves as an embellishment on temple walls or aesthetic purpose but is rarely an object of actual worship. A three-eyed Shiva with a moustache is rarely depicted and shows local geographical influence. His three eyes symbolize the sun, moon and fire. His fully open eyes are far from meditative. He has a snake cord around his neck showing the powers of Shiva to deal with death but also to hold the sexual energy of kundalini, the yogic serpent power. To hold his coiled hair in place, another serpent slides around it. Ganga emerges from his hair in a human form and also as a stream of water flowing down.
The Brahmapurana, one of the earliest Puranas, mentions that Shiva was so fond of goddess Ganga that he had placed her in his hair to honour her better. This was the constant reason for envy between Parvati and Ganga till the latter flowed down to the earth.
This description by Renu Rana.
Of Related Interest: