Slaying of Demon Vakrasura & Manifestation of Vakra Kali
According to the Sthala Puranam, an atrocious demon named Vakrasura obtained an extraordinary boon from Lord Shiva through intense penance: that no mortal, weapon, or god could slay him unless Lord Shiva Himself intervened. Emboldened by this invincibility, Vakrasura tormented the devas, rishis, and sages. Seeking relief, the celestial beings prayed to Lord Vishnu and Lord Shiva.
Lord Vishnu engaged Vakrasura in fierce battle and decapitated him using His divine discus, the Prayoga Chakra. However, Vakrasura's sister, Dhunmukhi, possessed the magical ability to generate thousands of demons from every drop of blood that fell to the earth. To stop Dhunmukhi, Goddess Parvati assumed her fierce form as Vakra Kali and drank every drop of Dhunmukhi's blood before it could touch the ground, eradicating the demoness. Having consumed the demoness's blood, Vakra Kali was overwhelmed with wrath (Ugra). To pacify Her, Lord Shiva manifested in front of Her as Chandramouleswarar, placing the gentle moon on His crest, thereby calming Her divine fury.
The Legend of the Vakra Lingam & Offset Geometry
Because Vakrasura worshipped Lord Shiva by placing the Lingam in an unusual angle, the Lingam assumed a unique three-faced form facing North (Mukha Lingam), known as Vakra Lingam. Uniquely, during the summer months, the Lingam turns cool and secretes tiny moisture droplets, while during cold winter months, the Lingam remains warm to the touch. Furthermore, every structural element of this temple—the main Rajagopuram entrance, the Nandhi statue, the sanctum axis, and the Saturn idol—is deliberately offset ('Vakra') from a straight linear alignment.
Nayanmar Visits & Tevaram Miracles
In the 7th century CE, the child-saint Thirugnanasambandar visited Thiruvakkarai. Overwhelmed by the Lord's presence and the pacified grace of Goddess Vakra Kali, he sang 11 sublime Tevaram verses praising Chandramouleswarar as the supreme cosmic healer who liberates devotees from all physical, mental, and planetary afflictions (Vakra Doshams).