Yaamuna Muni – known as Aala Vandhaar – was the grandson of Natha Muni and son of Iswara Bhattaazhwan and Ranganayaki. He is considered the Amsam of Simhavahana, one of the Nithyasuris in Paramapada by some and some otheres hold him to be the manifestation of Harivakthra, another Nithyasuri.

His date of birth is given as 917 AD (Kali Yuga 4017) and he was born in the year Dhaathu, Adi month, in the constellation of Uththiraadam on a Friday. His place of birth is Kuppankuzhi (2 kms from Kaattu Mannaar Koil-Veeranarayana Puram). He was named Yamunai-Thuraivan – Yaamuna for short. The boy grew apace, a marvel of loveliness and intelligence. He learned all branches of knowledge, both secular and spiritual.

Once, a haughty royal chaplain by name Akkiyaazhwan was challenging and humiliating learned men. Yaamuna accepted the challenge and went to the court to argue with him. The queen was so impressed with the boy that she prevailed upon the king to give him half the kingdom if he won in the debate offering herself to be thrown to wild dogs, if the boy failed.

Akkiyaazhwan asked the boy to state three propositions positive or negative which he offered to counter. And, if he could not, the boy would be declared the winner. Yaamuna posed thus:

• Your mother is not a barren woman.
• The king is a righteous and powerful ruler.
• The queen is a model of chastity.

By no stretch of imagination could Akkiyaazhwan affirm that his mother was barren, by no assumption of courage could he call the king wicked and powerless and no way could he allege that the queen was unchaste. He hung his head in shame. The King now asked Yaamuna to disprove his own statements.

Yaamuna clarified by observing the following:

• The sacred laws say that an only son is no son at all. So, Akkiyaazhwaan's mother was as good as barren in the eyes of the law.
• The king cannot be called righteous when he entertained such an arrogant person to be his chaplain and his not dismissing the chaplain showed that the king was indeed powerless.
• According to the Sruthi texts, every woman is wedded first to Soma, then Gandharva and then Agni before marrying her earthly partner. The queen was no exception and therefore cannot be deemed a model of chastity.

The King fired Akkiyaazhwan and gave Yamuna half his kingdom as promised to the queen. The queen hailed the boy as 'Aala Vandhaar' (one who came to save me). Thus, Aala Vandhaar entered his royal career in right earnest. But the royal duties demanded his attention so much that he could not attend even to the religious duties properly.

Meanwhile, Rama Misra (Manakkaal Nambi) was trying to carry out his promise to his Guru to install Aala Vandhaar as the spiritual successor to Natha Muni. But, he could not get an audience with Aala Vandhaar, the king, to discuss the matter. He hit upon a curious plan. He made friends with the servants in the royal kitchen and through them learned that Aala Vandhaar relished a special variety of spinach called ‘Thoodhu Valai Keerai’. He started supplying the spinach daily. After a period of about six months he suddenly stopped deliveries. Aala Vandhaar enquired why the spinach was not being served. The servants replied that an old man who used to supply had suddenly not turned up. He ordered that the old man be brought before him when he visited the next time. The very next day Rama Misra appeared and was duly taken to the king.

During this session, Rama Misra explained the purpose of his mission and requested Aala Vandhaar to take over the reins of spiritual leadership bequeathed to him by his illustrious grandfather, Natha Muni. Aala Vandhaar took to Sannyasa and was thenceforward known as Yaamuna Muni.

He is the one who composed the earliest Shtothras of Srivaishnava Sampradaya as he wrote several works that are lofty in content and simple in style. They include: 1. Chathu Sloki, 2. Sthothra Rathnam, 3. Siddhi-thrayam (consisting of Athma Siddhi, Samvith Siddhi and Easwara Siddhi), 4. Agama Pramanya, 5. Maha Purusha Nirnayam, and 6. Githartha Sangraham.

Swami Desika pays homage to Yaamuna thus:

“Aala Vandhaar, who learned Vedantha Arthas at the feet of Manakkaal Nambi, was not only the one residing on the banks of Yamuna (Yamunai Thuraivan) by name but was also like the clear flowing waters of the river Yamuna. Lord Krishna got rid of the cruel Kaalinga from the river and made its water pure and clear for all to drink. He was most delighted when he played with the Gopis of Brindhaavanam in the Yamuna waters. Likewise, Aala Vandhaar vanquished those who misinterpreted the Vedas and established Vedantha Siddhantha. Just as one can derive supreme pleasure by bathing in the holy waters of Yamuna, one can enjoy supreme Bhagavath Gunaanubhava by immersing in the lucid Granthas of Yaamuna.”

Periya Nambi, also known as Maha Purna, was born as the Amsam of Kumudhaakshara, one of the Nithyasuris. His year of birth is placed as 998 AD (Hevilambi year, Margazhi month and in the constellation of Kettai) on a Wednesday. Not much is known about him except that he was the direct disciple of Aala Vandhaar and that it was he who did Pancha Samskaram to and destined to become the principal Acharya of Sri Ramanuja.

At the same time, the Lord of Kanchi bade one ThirukKachchi Nambi to send Ramanuja to Periya Nambi at Srirangam to learn Vedantha Arthas. In deference to this, Ramanuja set forth towards Srirangam. Both Ramanuja and Periya Nambi met with each other at Maduranthakam. Having recounted their mutual experiences, Periya Nambi performed the Pancha Samskaram to Ramanuja there itself.

Swami Desika pays his respects to Maha Purna thus:

“When there was a danger from other faiths to Visishtaadhvaita Siddhantha, Lord Thiruvarangan commanded Periya Nambi ‘whatever you have learned from Aala Vandhaar, you pass on to Ramanuja who is in Kanchi and through him arrange for the growth of the Siddahantham’”. Periya Nambi immediately set out to Kanchi to carry out the command and performed Pancha Samskaaram and Upadhesam to Ramanuja of all that he had learned at the feet of Aala Vandhaar. Thus, Periya Nambi fulfilled the wishes of Periya Perumal and by initiating Ramanuja, paved the way for the redemption of our Siddhantha once again. I take refuge at the feet of this all-round master (Desikam Purnam) who fulfilled the wishes of Lord Vishnu.”