The Lord Shiva in his manifestation of formlessness is worshiped in Chidambaram. The Lord is said to continuously dance in a state of eternal bliss "Aananda thaandava", with his consort Sakthi or energy called Sivagami and is diagrammatically represented by a Yantra on the wall of an empty space in the sanctum sanctorum of the temple. A curtain covers this space which when drawn reveals strands of golden 'Vilva' leaves hung to indicate the Lord's presence. The curtain is dark in the exterior (indicating ignorance) and bright red in the interior (indicating wisdom and bliss). 

 

During the daily rituals, the Chief priest of the day, himself in a state of Godliness - Shivahambhava (Shiva - the Lord, hum – me / us, bhava - state of mind), withdraws the curtain indicating the withdrawal of ignorance and reveals the space, and the Lord's presence. The Chidambara Rahasya, is hence that when in total surrender, one lets God intervene and remove ignorance, one gets to see and experience his presence and hence bliss.