Three in One

Sage Parasara sprayed the nectar he obtained from the milk ocean in the Manimutha River, built a hermitage on the river bank and was performing penance.  Three demons

1. Thanjakan, 
2. Thandakan and 
3. Tharasura with their deathless boon granted by Lord Shiva began to harass the sage and others performing penance with him.  

The sage advised them to shed their demon traits and reform themselves.  They turned a deaf year. The sage appealed to Lord Shiva for protection.  Shiva sent Kalidevi to destroy them.  But they drank the nectar mixed river water and came back alive to continue their atrocities.  Sage approached Lord Vishnu.

1. Mahavishnu took the Narasimha form and defeated Thanjaka who took the elephant form.  Lord placed the demon on His lap to kill him when he gained wisdom and shed his cruel traits.  He also begged the Lord to stay in the place and bless all.  He also begged that the place should be named after him.  His boon granted, the place came to be known as Thanjamapuri. 
2. Seeing the defeat of Thanjaka, Thandakan hid himself under the earth.  Lord became a Varaha, entered the hiding and killed the demon.  
3. Tharaka was killed by Kali.  

After the destruction of the three demons, Lord appeared before Sage Parasara as Neelamega Perumal.  Lord is gracing this place in three names in three separate temples.

Lord Vishnu who destroyed the demons graces in three separate temples as 

1. Neelamegar, 
2. Manikundra Perumal and 
3. Veera Narasimha in three forms. 

Saints Boodhathazhwar and Tirumangai Azhwar had sung the glory of the three Perumals together in their hymns. The three temples form a single Divya Desa.

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