The philosophical construct of Srivaishnavism which taught that prapatti is the easiest and quickest means to salvation, was elaborated by many stalwart acharyas such as Srimad Yamunacharya, Bhagavad Ramanuja and Srimad Vedanta Desika.
After Nathamuni, it was Yamuna, his grandson, who systematically introduced the doctrine of self-surrender through works such as the Stotra Ratna, where he explains that the path of loving self-surrender or sharanagati is open for one who is unable to follow the path of action or karmayoga, the path of knowledge or jnanayoga and the path of devotional love or bhaktiyoga, and thus has no other way of salvation. In the Stotra-ratna, Yamuna therefore seeks protection from the Lord in a state of complete helplessness and total dependence, and declares that the Lord is his only refuge.
Ramanuja whose Sharanagati Gadyam is an exposition and expansion of the philosophy of prapatti penned by Yamuna in the Stotra-ratna, introduces a ritualized version of prapatti that specifically addresses those who are ineligible for practicing the different kinds of yogas. Srivaishnavism thus offered a soteriology that included everyone who was incapable of Vedic study through birth or qualification, or those who were mired in illusory entanglements, and could not extricate themselves from a life of sin.
Srivatsya Varada Guru, a twelfth century preceptor, known popularly as Nadadoor Ammal in his Prapanna-parijata explains that prapatti is not a new concept but has its roots in the Vedas. The vasuranya mantra of the Taittiriya section of the Krishna Yajurveda mentions prapatti by the name ‘nyasa’, the act of giving oneself up to the Lord, and also describes the procedure for performing prapatti.
An often quoted definition of prapatti composed by Nadadoor Ammal in the Parijata is a fervent plea to the Lord, where he says: “I am the abode of all sins, utterly helpless and without any other recourse. O Lord! You alone are my means to salvation! Such a condition of the mind is called prapatti.”
In the post-Ramanuja period, many of his immediate successors produced a vast range of prapatti literature in Sanskrit, Tamil and Manipravala. They usually took the form of praise-forms or stotras, elaborate commentaries or vyakhyanams and poetic-epics or maha-kavyams. There are over forty commentaries on the Nalayira Divya-prabandham alone, with a vast ocean of other literature on prapatti that has been composed since then.
Amongst Ramnuja’s successors, it was Vedanta Desika who emerged as the greatest guardian and proponent of Sri Vaishnavism through his elaborate commentaries and compositions that enshrine the significance of prapatti in all its aspects. The primary book in which he has elaborated the deeper internal mysteries of prapatti is the ‘Rahasyatrayasara’. He has also independently established the supremacy of prapatti through other compositions in Sanskrit and Tamil such as Tatparya-tika, Gitasara, Nyasa-vimshati, Nyasa-tilaka, Nyasa-dashakam, Nikseparaksha and Adaikkalappattu. Further, Vedanta Desika analyses the Saranagati Gadyam of Ramanuja by comparing the verses with each word of the three great Sri Vaishnava mantras: the mulamantra, the dvayam and the charamasloka.
We can see therefore that the literature of prapatti was available before Sri Vedanta Desika in a cryptic form. However, it was Vedanta Desika who elaborated, reaffirmed, consolidated and simplified the doctrinal tenets of prapatti. He points to reassurances given by the Supreme Lord to the surrendered jiva: when the jiva is in despair or grief because he is not able to adopt certain upayas or methods which are prescribed as productive for one’s salvation, then the Lord promises to stand up as those upayas and guarantee the result of salvation.