The Deity here was installed by Vararuchi about 1500 years ago. This is a small temple and must have been renovated a few times. It is standing on a hill and by the side of this temple there is a temple for Thirumandhamkunnu Bhagavathi.King Vikramadithya once asked Vararuchi as to which passage in Ramayana is the best. He replied that the advice given by Urmila to her husband Laxmanan was the best. It is reproduced below.
"Consider Rama as if he were your father, Seetha as your mother and the forest as Ayodhya."
He received a number of presents from Vikramadithya . He also had a premonition that he will marry a Paraya girl and that he could also identify his future wife in a child. He picked up the child, put her in a boat and floated her in a river. He then came to south to avoid the girl.
One day, many years later, Vararuchi, during one of his travels, went into a poor Brahmin’s house for food. When Vararuchi set some preconditions (in code language) for taking food there, a girl from inside assured that all the conditions will be met.
Thereupon Vararuchi proclaimed ex-communication for himself from the Brahmin community and along with his wife, started on a pilgrimage. During Vararuchi's travels along the Nila river, (Bharathapuzha) his wife gave birth to 12 children. Each time she delivered a child, he asked her if the baby had a mouth. If she said yes, he would say, "God will feed it if it has a mouth", and would ask her to leave the child there.
Grieved by these, when the 12th child was born, she lied and reported that the baby did not have a mouth, upon which he permitted her to take the child along. But when she was about to breast-feed it, she found that the baby actually did not have a mouth.Vararuchi then deified the child on a hill, which is called "Vaayilyakkunnilappan" (Hill Lord without mouth), at Thiruvazhiyode near Kadampazhipuram (in the present Palakkad district). The children left out in the forest were subsequently found, adopted and raised by families belonging to different communities, recognised one another as they grew up, and used to get together at the Illam (residence) of the eldest son, Mezhathol Agnihothri,every year on their father Vararuchi's death anniversary (Sraadham).
According to legend, these 12 sons were: Mezhathol Agnihothri (Brahmin), Paakkanaar (Parayan), Rajakan (Washerman), Naaraanathu Bhraanthan (Elayathu), Kaarakkal Maatha (high caste Nair), Akavoor Chaathan (Vysyan), Vaduthala Nair (Nair soldier), Vallon (Thiruvalluvar) , Uppukottan (Mlecha), Paananaar (Paanan), Perumthachan (Carpenter ,who built a no of temples), Vaayillaakkunnilappan (deity).
Some of these twelve families still exist in the southern part of Palakkad district (Shornur, Pattambi and Thrithaala areas). Recently, on November 30, 1997, most of them met in Vemanchery Mana, the Illam (residence) of Mezhathol Agnihothri, near Thrithaala. (Source: Namboothiri Website)