The mantle of the leadership of the Vaishnavas fell by common consent upon the shoulders of this teacher, who was a married man and led the life of a householder. He lived in the age of the early great Cholas and the age was one of great religious ferment, the outward exhibition of which in India took the form of controversial activity. Yamunacharya comes into prominence as the result of a successful controversy that he held against a Saiva. He was a great dialectician and indisputably secured success by a clever stroke. His opponent seems rather too foolishly to have undertaken to establish the contrary of whatever Yamuna would state categorically. The Vaishnava turned the tables upon him by making three statements. (1) "The king who was presiding over the controversy was a Sarvabhauma, (2) the queen who was seated by him was unquestionably chaste, and (3) the mother that gave birth to him (the Saiva champion) was certainly not a barren woman." The establishment of the categorical negative of these statements was obviously impossible. But the story has it that he controverted him successfully, even on questions of philosophy and religion, and established his position at the court. As the wager of the controversy he obtained the means to live in comfort, and even in some affluence, and that put him beyond the need of earning a livelihood. He lived to a ripe old age and obtained as the bequest of his grand-father all that was worth learning of the Vaishnava philosophy and religion from the successors of Nathamuni. The one thing that remained uncompleted at the latter end of his life was the provision of a successor to continue the Vaishnava teaching and organisation. He looked about and found a suitable young man in a great-grandson of his who was undergoing education at Kanchi. While still under his teacher the young man had made such an impression, that his reputation had already reached the ears of the saintly old Acharya in Srirangam. The venerable old man undertook a journey to Conjeevaram to see if reputation spoke true of the achievements of Ramanuja, and the story has it that he caught sight of the young man in the company of his fellow disciples and the great teacher Yadavaprakasa in the enclosure of the great Vishnu temple at Kanchi.. The site at which Alavandar caught the first glimpse of his successor is yet pointed out by the old residents of the town.

1 Ins. of Raja Raja III, at Tiruvorriyur, Ep. Rep,, 1912, No, 211.