Ayyaval of Tiruvisanallur was a great Siva - bhakta and a pioneer in spreading Nama-siddhanta in South India. Apart from the hymns of exquisite beauty and moving devotion he composed, he also wrote a work on the Doctrine of the Name (Namasiddhanta).
The name of the work was Bhagavan-nama-bhusana. Although no manuscript copy of work is available, it is quoted thrice by Bodhendra, in his work, 'Namamrta-rasayana,' which is it self patterned after Ayyaval's work. Bodhendra, also known as Bhagavan-nama Bodhendra, was the fifty-ninth in succession to the Sri Kanchi-kamakoti-Pitha, and was a great leader, along with Ayyaval, of the movement for propagating the gospel of the Divine Name.
It is said that before he became a sannyasin Bodhendra recovered, during his extensive travels in the North, the text of Bhagavan- nama- kaumudi from the family of its renowned author Laksmidhara, who had prophesied that a great sannyasin would become the instrument for spreading the faith in the Divine Name in the Southern country.
The efficacy of the Divine Name constitutes the central teaching of Nama-siddhanta. Laksmidhara, and following him, Bodhendra and AyyavaI stress the importance of repeating the Name of the Divine as a potent discipline for securing liberation. The basic authorities for setting forth this discipline are not only the Puranas, but the Vedas themselves.
In his Namamrta-rasayana, Bodhendra offers six reasons for showing that the utterance of the Divine Name is superior to the other disciplines taught in the scriptures. In the first place, the repetition of the Name, which is open to all irrespective of caste, stage in life, and sex, involves no injury to any living being. Secondly, it does not stand in need of any ancillary aid. Thirdly, in producing its result, it does not require the intercession of a third person.
Fourthly, its practice is not conditioned by the time factor; nama-japa can be performed at any tune Fifthly, there are no restrictions in regard to place. And, sixthly, there are no ritualistic regulations for practicing the repetition of the Divine Name. Although there are no extraneous restrictions in regard to the practice of nama-sadhana, the sadhaka, however, should not be guilty of certain Offences, which are offences against the Name itself (nama-aparadha).