As per Hindu legend, sage Suthapas was taking bath in Nupura Ganga at Azhagar Hill and did not pay heed to sage Durvasa, who was passing by.
The enraged Durvasa cursed Suthapas that he would turn into a frog until he is redeemed of his curse by Sundararajar, who is also known as Kallazhagar.
Suthapas Maharishi, who is named as ‘Manduka maharisi’ because of his frog form, performed penance on the banks of river Vaigai, which is otherwise known as Vegavathi, at Thenur.
Kallazhagar descended from his abode in Azhagar Hill to redeem Manduka Maharishi off his curse.
Since days unknown, it is believed that Kallazhagar comes to Thenur via Malaipatti, Alanganallur and Vayalur.
In Thenur Mandap, the lord redeems the sage of his curse and leaves for his abode. "
During Thirumalai Nayak regime (1623 to 1659 AD), in 1653 the Manduka Maharishi relieving ritual was shifted to Vandiyur village where the event is performed at Thennur Mandapam, built by Thirumalai Nayak himself,".

As per another Hindu legend, the presiding deity was worshiped by Yama, the god of death.
He requested Vishnu to stay in the place and built a temple with the help of Vishwakarma, the divine architect.
As per Hindu legend, sage Suthapas was taking bath in Nupura Ganga at Azhagar Hill and did not pay heed to sage Durvasa, who was passing by. The enraged Durvasa cursed Suthapas that he would turn into a frog until he is redeemed of his curse by Sundararajar, who is also known as Kallazhagar. Suthapas Maharishi, who is named as ‘Manduka maharisi’ because of his frog form, performed penance on the banks of river Vaigai, which is otherwise known as Vegavathi, at Thenur. Kallazhagar descended from his abode in Azhagar Hill to redeem Manduka Maharishi off his curse. Since days unknown, it is believed that Kallazhagar comes to Thenur via Malaipatti, Alanganallur and Vayalur. In Thenur Mandap, the lord redeems the sage of his curse and leaves for his abode. "During Thirumalai Nayak regime (1623 to 1659 AD), in 1653 the Manduka Maharishi relieving ritual was shifted to Vandiyur village where the event is performed at Thennur Mandapam, built by Thirumalai Nayak himself,".
As per another Hindu legend, the presiding deity was worshiped by Yama, the god of death. He requested Vishnu to stay in the place and built a temple with the help of Vishwakarma, the divine architect.
Kallazhagar temple