During the Wedding of Lord Shiva with Mother Parvathi in Mount Kailas, Sage Agasthya was in south performing Shiva Puja in this place. Two demon brothers Vilvalan and Vatapi caused hindrance to his puja. Agasthya killed them with his penance power and incurred the Brahmmahati dosha-a sin caused by killing others, good or bad. He worshipped Lord Shiva here for relief from the dosha and also relief from any disturbance to perform his pujas. Lord deputed Veerabadra to help the sage. Lord Veerabadra protected Sage Agasthya and also relieved the sage from the dosha. He thus has His due place in the temple. As sage Agasthya worshipped Lord here, He is praised as Lord Agastheeswarar and is the presiding deity of the temple.
When Lord Shiva granted darshan to Sage Agasthya with Mother Parvathi, Ambica was wearing golden ornaments, hence She is praised as Swarnambika. The shrines of Mothers Mahalakshmi and Saraswathi are before the shrine of Ambica. The Navagraha Mandap is on the opposite side. As Sage Agasthya destroyed demons Vilvalan and Vatapi in this place, it is named Villivakkam. Agasthya’s destroying of the demons event is celebrated during the Vaikasi Brahmmotsavam of the temple.
Lord Veerabadra graces from a separate temple at the southern entrance of Lord Agastheeswara temple. He appears with two sharp teeth with a Danda in His left hand. Daksha is before Him in a bowing form. Mother Badrakali shrine is in the front mandap. As Lord Veerabadra is another form of Lord Shiva, Pradosha pujas and one time puja on the Shivarathri day are dedicated to Him. Lord Veerabadra is facing north, the direction of Kubera the Lord of Wealth. People pray here seeking prosperity boon. Hence, He is praised as Ishwarya Veerabadra.
Planet Mars created a spring here and worshipped Lord Shiva for relief from a curse. This spring-theertha is outside the temple. Hence, the temple is also famous as a Mars – Angaraka Parihara Sthala. Lord Valampuri Vinayaka is nearby facing north. Devotees call this temple as Sevvai Temple – Sevvai-Mars. Lord Shiva granted darshan to sage Agasthya on a Tuesday (Sevvai day in Tamil). On Tuesdays of Aadi month (July-August), special pujas are dedicated to Lord and Mother.