Sowmiya Narayana Perumal Temple, Thirukoshtiyur – Religious Significance
Sowmya Narayana Perumal temple is revered in Nalayira Divya Prabhandam, the 7th – 9th century Vaishnava canon, by Periazhwar, Thirumalisai Alvar Bhoothathazhwar and Peyazhwar. The temple is classified as a Divyadesam, one of the 108 Vishnu temples that are mentioned in the book. During the 18th and 19th centuries, the temple finds mention in several works like 108 Tirupathi Anthathi by Divya Kavi Pillai Perumal Aiyangar.
The temple is known as the place where Ramanuja, the expounder of Vaishnavadatta philosophy preached the holy Ashtakshara "Ohm Namo Narayana" to all people irrespective of their caste. Thirukoshtiyur Nambigal, the teacher of Ramanuja, taught him the gospel and instructed him not to reveal it to anyone. Taking the risk of his life, Ramanuja climbed up the temple and revealed the verse to the whole world. Nambigal was pleased by the spirit of Ramanuja and named him Emperumanar (meaning my superior). Following the event, a life size image of Ramanuja was housed in the Ashtanga Mandap of the temple.