Sri Ramanuja Munaye Namaha,
Sri Velukkudi Krishnan Swami Guruvae Namaha,
Nandri BhagavAta for the understanding.
In short, Swami has said,
Athma in this leela vibhoothi (Presently all of us) are called as BhaddhaAthmas. Means, Pure Athma covered with “Karmas, Kaalam and Prakruthi”.
The actions that we do, results in Phalam either good or bad karmas. All these karmas are stored in BhagavAn Sriman Narayanan’s THIRU ULLAM (heart/mind) as Sanchita Karmas (unlimited bags of karmas), which bhagavan pulls one bag and give it to us as ‘prarabtha jarmas’ to relinguish for 10 janmas. But due to ‘Ruchi and Vasana’ which us stored in Athma, we keep accumulating more karmas (either do sins or punya) and is never ending process, like a frog inside a well, jumping 2 inches high and falling 3 inches backwards. It can never come out of the well by its own effort. It needs an external help from outside the well, like Acharya Ramanujar to uplift us from this well (samsaram). So, only bhagavan has access to erase it. HE does erases the sanchita karma for a Sharanagathan (Thann ThiruvAdiyai nambhi iruppavargalukku)
The remaining prarabtha karma of this janma has to be experienced by us, but bhagavAn reduces the intensity for a sharanagathan and at some point in this janma, HE cuts off that Prarabtha karma and takes the Sharanagathan to SriVaikuntam as he/she are involved in kainkaryams/bhagavat anubhavam based on their yatha shakthi (to be ability of what we possess).
Swami explains it all in the above upanyassm.
Swami Thiruvadiyil Kainkaryame ParamaPurushartham.
Adiyen Sri Velukkudi Krishna Dasan,
Uyya Oraey Vazhi UdayavAr ThiruvAdi,
Sarvam SriKrishna Kudumbham.